diff --git a/app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt b/app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt
index 2ee0ae8..e6fd89f 100644
--- a/app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt
+++ b/app/src/main/java/it/danieleverducci/lunatracker/MainActivity.kt
@@ -297,7 +297,7 @@ class MainActivity : AppCompatActivity() {
         d.setView(dialogView)
 
         val tempSlider = dialogView.findViewById<Slider>(R.id.dialog_temperature_value)
-        val range = NumericUtils(this).getValidEventQuantityRange(LunaEvent.TYPE_TEMPERATURE)!!
+        val range = NumericUtils(this).getValidEventQuantityRange(LunaEvent.Type.TEMPERATURE)!!
         tempSlider.valueFrom = range.first.toFloat()
         tempSlider.valueTo = range.second.toFloat()
         tempSlider.value = if (event.quantity == 0) {
@@ -537,7 +537,7 @@ class MainActivity : AppCompatActivity() {
     }
 
     fun askNotes(event: LunaEvent, showTime: Boolean, onPositive: () -> Unit) {
-        val useQuantity = (event.type != LunaEvent.TYPE_NOTE && event.type != LunaEvent.TYPE_CUSTOM)
+        val useQuantity = (event.type != LunaEvent.Type.NOTE)
 
         val d = AlertDialog.Builder(this)
         val dialogView = layoutInflater.inflate(R.layout.dialog_edit_notes, null)
@@ -759,7 +759,7 @@ class MainActivity : AppCompatActivity() {
         val updateValues = {
             quantityTextView.text = NumericUtils(this).formatEventQuantity(event)
             notesTextView.text = event.notes
-            if (event.type == LunaEvent.TYPE_SLEEP && event.quantity > 0) {
+            if (event.type == LunaEvent.Type.SLEEP && event.quantity > 0) {
                 dateEndTextView.text = DateUtils.formatDateTime(event.time + event.quantity)
                 dateEndTextView.visibility = View.VISIBLE
             } else {
@@ -781,22 +781,28 @@ class MainActivity : AppCompatActivity() {
 
         quantityTextView.setOnClickListener {
             when (event.type) {
-                LunaEvent.TYPE_BABY_BOTTLE -> askBabyBottleContent(event, false, updateValues)
-                LunaEvent.TYPE_WEIGHT -> askWeightValue(event, false, updateValues)
-                LunaEvent.TYPE_DIAPERCHANGE_POO,
-                LunaEvent.TYPE_DIAPERCHANGE_PEE,
-                LunaEvent.TYPE_PUKE -> askAmountValue(event, false, updateValues)
-                LunaEvent.TYPE_TEMPERATURE -> askTemperatureValue(event, false, updateValues)
-                LunaEvent.TYPE_NOTE -> askNotes(event, false, updateValues)
-                LunaEvent.TYPE_SLEEP -> askSleepValue(event, updateValues)
+                LunaEvent.Type.BABY_BOTTLE -> askBabyBottleContent(event, false, updateValues)
+                LunaEvent.Type.WEIGHT -> askWeightValue(event, false, updateValues)
+                LunaEvent.Type.DIAPERCHANGE_POO,
+                LunaEvent.Type.DIAPERCHANGE_PEE,
+                LunaEvent.Type.PUKE -> askAmountValue(event, false, updateValues)
+                LunaEvent.Type.TEMPERATURE -> askTemperatureValue(event, false, updateValues)
+                LunaEvent.Type.NOTE -> askNotes(event, false, updateValues)
+                LunaEvent.Type.SLEEP -> askSleepValue(event, updateValues)
+                else -> {
+                    Log.w(TAG, "Unexpected type: ${event.type}")
+                }
             }
         }
 
         notesTextView.setOnClickListener {
             when (event.type) {
-                LunaEvent.TYPE_FOOD,
-                LunaEvent.TYPE_MEDICINE,
-                LunaEvent.TYPE_NOTE -> askNotes(event, false, updateValues)
+                LunaEvent.Type.FOOD,
+                LunaEvent.Type.MEDICINE,
+                LunaEvent.Type.NOTE -> askNotes(event, false, updateValues)
+                else -> {
+                    Log.w(TAG, "Unexpected type: ${event.type}")
+                }
             }
         }
 
diff --git a/app/src/main/java/it/danieleverducci/lunatracker/adapters/LunaEventRecyclerAdapter.kt b/app/src/main/java/it/danieleverducci/lunatracker/adapters/LunaEventRecyclerAdapter.kt
index e328066..3090c52 100644
--- a/app/src/main/java/it/danieleverducci/lunatracker/adapters/LunaEventRecyclerAdapter.kt
+++ b/app/src/main/java/it/danieleverducci/lunatracker/adapters/LunaEventRecyclerAdapter.kt
@@ -54,12 +54,11 @@ class LunaEventRecyclerAdapter: RecyclerView.Adapter<LunaEventRecyclerAdapter.Lu
         // Contents
         holder.type.text = item.getTypeEmoji(context)
         holder.description.text = when (item.type) {
-            LunaEvent.TYPE_MEDICINE -> item.notes
-            LunaEvent.TYPE_NOTE -> item.notes
-            LunaEvent.TYPE_CUSTOM -> item.notes
+            LunaEvent.Type.MEDICINE -> item.notes
+            LunaEvent.Type.NOTE -> item.notes
             else -> item.getTypeDescription(context)
         }
-        val endTime = if (item.type == LunaEvent.TYPE_SLEEP) {
+        val endTime = if (item.type == LunaEvent.Type.SLEEP) {
             item.quantity + item.time
         } else {
              item.time
@@ -68,7 +67,7 @@ class LunaEventRecyclerAdapter: RecyclerView.Adapter<LunaEventRecyclerAdapter.Lu
         var quantityText = numericUtils.formatEventQuantity(item)
 
         // if the event is weight, show difference with the last one
-        if (item.type == LunaEvent.TYPE_WEIGHT) {
+        if (item.type == LunaEvent.Type.WEIGHT) {
             val lastWeight = getPreviousWeightEvent(position)
             if (lastWeight != null) {
                 val differenceInWeight = item.quantity - lastWeight.quantity
@@ -99,7 +98,7 @@ class LunaEventRecyclerAdapter: RecyclerView.Adapter<LunaEventRecyclerAdapter.Lu
             return null
         for (pos in startFromPosition + 1 until items.size) {
             val item = items.get(pos)
-            if (item.type != LunaEvent.TYPE_WEIGHT)
+            if (item.type != LunaEvent.Type.WEIGHT)
                 continue
             return item
         }
diff --git a/app/src/main/java/it/danieleverducci/lunatracker/entities/LunaEvent.kt b/app/src/main/java/it/danieleverducci/lunatracker/entities/LunaEvent.kt
index 63e268b..755ad8c 100644
--- a/app/src/main/java/it/danieleverducci/lunatracker/entities/LunaEvent.kt
+++ b/app/src/main/java/it/danieleverducci/lunatracker/entities/LunaEvent.kt
@@ -13,24 +13,74 @@ import java.util.Date
  */
 class LunaEvent: Comparable<LunaEvent> {
 
+    enum class Type {
+        BABY_BOTTLE,
+        FOOD,
+        BREASTFEEDING_LEFT_NIPPLE,
+        BREASTFEEDING_BOTH_NIPPLE,
+        BREASTFEEDING_RIGHT_NIPPLE,
+        DIAPERCHANGE_POO,
+        DIAPERCHANGE_PEE,
+        SLEEP,
+        WEIGHT,
+        MEDICINE,
+        ENEMA,
+        NOTE,
+        COLIC,
+        TEMPERATURE,
+        PUKE,
+        BATH,
+        UNKNOWN
+    }
+
     companion object {
-        const val TYPE_BABY_BOTTLE = "BABY_BOTTLE"
-        const val TYPE_WEIGHT = "WEIGHT"
-        const val TYPE_BREASTFEEDING_LEFT_NIPPLE = "BREASTFEEDING_LEFT_NIPPLE"
-        const val TYPE_BREASTFEEDING_BOTH_NIPPLE = "BREASTFEEDING_BOTH_NIPPLE"
-        const val TYPE_BREASTFEEDING_RIGHT_NIPPLE = "BREASTFEEDING_RIGHT_NIPPLE"
-        const val TYPE_DIAPERCHANGE_POO = "DIAPERCHANGE_POO"
-        const val TYPE_DIAPERCHANGE_PEE = "DIAPERCHANGE_PEE"
-        const val TYPE_MEDICINE = "MEDICINE"
-        const val TYPE_ENEMA = "ENEMA"
-        const val TYPE_NOTE = "NOTE"
-        const val TYPE_CUSTOM = "CUSTOM"
-        const val TYPE_COLIC = "COLIC"
-        const val TYPE_TEMPERATURE = "TEMPERATURE"
-        const val TYPE_FOOD = "FOOD"
-        const val TYPE_PUKE = "PUKE"
-        const val TYPE_BATH = "BATH"
-        const val TYPE_SLEEP = "SLEEP"
+        fun getTypeEmoji(context: Context, type: Type): String {
+            return context.getString(
+                when (type) {
+                    Type.BABY_BOTTLE -> R.string.event_bottle_type
+                    Type.WEIGHT -> R.string.event_weight_type
+                    Type.BREASTFEEDING_LEFT_NIPPLE -> R.string.event_breastfeeding_left_type
+                    Type.BREASTFEEDING_BOTH_NIPPLE -> R.string.event_breastfeeding_both_type
+                    Type.BREASTFEEDING_RIGHT_NIPPLE -> R.string.event_breastfeeding_right_type
+                    Type.DIAPERCHANGE_POO -> R.string.event_diaperchange_poo_type
+                    Type.DIAPERCHANGE_PEE -> R.string.event_diaperchange_pee_type
+                    Type.MEDICINE -> R.string.event_medicine_type
+                    Type.ENEMA -> R.string.event_enema_type
+                    Type.NOTE -> R.string.event_note_type
+                    Type.TEMPERATURE -> R.string.event_temperature_type
+                    Type.COLIC -> R.string.event_colic_type
+                    Type.FOOD -> R.string.event_food_type
+                    Type.PUKE -> R.string.event_puke_type
+                    Type.BATH -> R.string.event_bath_type
+                    Type.SLEEP -> R.string.event_sleep_type
+                    Type.UNKNOWN -> R.string.event_unknown_type
+                }
+            )
+        }
+
+        fun getTypeDescription(context: Context, type: Type): String {
+            return context.getString(
+                when (type) {
+                    Type.BABY_BOTTLE -> R.string.event_bottle_desc
+                    Type.WEIGHT -> R.string.event_weight_desc
+                    Type.BREASTFEEDING_LEFT_NIPPLE -> R.string.event_breastfeeding_left_desc
+                    Type.BREASTFEEDING_BOTH_NIPPLE -> R.string.event_breastfeeding_both_desc
+                    Type.BREASTFEEDING_RIGHT_NIPPLE -> R.string.event_breastfeeding_right_desc
+                    Type.DIAPERCHANGE_POO -> R.string.event_diaperchange_poo_desc
+                    Type.DIAPERCHANGE_PEE -> R.string.event_diaperchange_pee_desc
+                    Type.MEDICINE -> R.string.event_medicine_desc
+                    Type.ENEMA -> R.string.event_enema_desc
+                    Type.NOTE -> R.string.event_note_desc
+                    Type.TEMPERATURE -> R.string.event_temperature_desc
+                    Type.COLIC -> R.string.event_colic_desc
+                    Type.FOOD -> R.string.event_food_desc
+                    Type.PUKE -> R.string.event_puke_desc
+                    Type.BATH -> R.string.event_bath_desc
+                    Type.SLEEP -> R.string.event_sleep_desc
+                    Type.UNKNOWN -> R.string.event_unknown_desc
+                }
+            )
+        }
     }
 
     private val jo: JSONObject
@@ -40,10 +90,16 @@ class LunaEvent: Comparable<LunaEvent> {
         set(value) {
             jo.put("time", value)
         }
-    var type: String
-        get(): String = jo.getString("type")
+    var type: Type
+        get(): Type {
+            return try {
+                Type.valueOf(jo.getString("type"))
+            } catch (_: Exception) {
+                Type.UNKNOWN
+            }
+        }
         set(value) {
-            jo.put("type", value)
+            jo.put("type", value.name)
         }
     var quantity: Int
         get() = jo.optInt("quantity")
@@ -81,13 +137,13 @@ class LunaEvent: Comparable<LunaEvent> {
         this.signature = event.signature
     }
 
-    constructor(type: String) {
+    constructor(type: Type) {
         this.jo = JSONObject()
         this.time = System.currentTimeMillis() / 1000
         this.type = type
     }
 
-    constructor(type: String, quantity: Int) {
+    constructor(type: Type, quantity: Int) {
         this.jo = JSONObject()
         this.time = System.currentTimeMillis() / 1000
         this.type = type
@@ -95,64 +151,24 @@ class LunaEvent: Comparable<LunaEvent> {
     }
 
     fun getTypeEmoji(context: Context): String {
-        return context.getString(
-            when (type) {
-                TYPE_BABY_BOTTLE -> R.string.event_bottle_type
-                TYPE_WEIGHT -> R.string.event_weight_type
-                TYPE_BREASTFEEDING_LEFT_NIPPLE -> R.string.event_breastfeeding_left_type
-                TYPE_BREASTFEEDING_BOTH_NIPPLE -> R.string.event_breastfeeding_both_type
-                TYPE_BREASTFEEDING_RIGHT_NIPPLE -> R.string.event_breastfeeding_right_type
-                TYPE_DIAPERCHANGE_POO -> R.string.event_diaperchange_poo_type
-                TYPE_DIAPERCHANGE_PEE -> R.string.event_diaperchange_pee_type
-                TYPE_MEDICINE -> R.string.event_medicine_type
-                TYPE_ENEMA -> R.string.event_enema_type
-                TYPE_NOTE -> R.string.event_note_type
-                TYPE_TEMPERATURE -> R.string.event_temperature_type
-                TYPE_COLIC -> R.string.event_colic_type
-                TYPE_FOOD -> R.string.event_food_type
-                TYPE_PUKE -> R.string.event_puke_type
-                TYPE_BATH -> R.string.event_bath_type
-                TYPE_SLEEP -> R.string.event_sleep_type
-                else -> R.string.event_unknown_type
-            }
-        )
+        return getTypeEmoji(context, type)
     }
 
     fun getTypeDescription(context: Context): String {
-        return context.getString(
-            when (type) {
-                TYPE_BABY_BOTTLE -> R.string.event_bottle_desc
-                TYPE_WEIGHT -> R.string.event_weight_desc
-                TYPE_BREASTFEEDING_LEFT_NIPPLE -> R.string.event_breastfeeding_left_desc
-                TYPE_BREASTFEEDING_BOTH_NIPPLE -> R.string.event_breastfeeding_both_desc
-                TYPE_BREASTFEEDING_RIGHT_NIPPLE -> R.string.event_breastfeeding_right_desc
-                TYPE_DIAPERCHANGE_POO -> R.string.event_diaperchange_poo_desc
-                TYPE_DIAPERCHANGE_PEE -> R.string.event_diaperchange_pee_desc
-                TYPE_MEDICINE -> R.string.event_medicine_desc
-                TYPE_ENEMA -> R.string.event_enema_desc
-                TYPE_NOTE -> R.string.event_note_desc
-                TYPE_TEMPERATURE -> R.string.event_temperature_desc
-                TYPE_COLIC -> R.string.event_colic_desc
-                TYPE_FOOD -> R.string.event_food_desc
-                TYPE_PUKE -> R.string.event_puke_desc
-                TYPE_BATH -> R.string.event_bath_desc
-                TYPE_SLEEP -> R.string.event_sleep_desc
-                else -> R.string.event_unknown_desc
-            }
-        )
+        return getTypeDescription(context, type)
     }
 
     fun getDialogMessage(context: Context): String? {
         return context.getString(
             when(type) {
-                TYPE_BABY_BOTTLE -> R.string.log_bottle_dialog_description
-                TYPE_MEDICINE -> R.string.log_medicine_dialog_description
-                TYPE_TEMPERATURE -> R.string.log_temperature_dialog_description
-                TYPE_DIAPERCHANGE_POO,
-                TYPE_DIAPERCHANGE_PEE,
-                TYPE_PUKE -> R.string.log_amount_dialog_description
-                TYPE_WEIGHT -> R.string.log_weight_dialog_description
-                TYPE_SLEEP -> R.string.log_sleep_dialog_description
+                Type.BABY_BOTTLE -> R.string.log_bottle_dialog_description
+                Type.MEDICINE -> R.string.log_medicine_dialog_description
+                Type.TEMPERATURE -> R.string.log_temperature_dialog_description
+                Type.DIAPERCHANGE_POO,
+                Type.DIAPERCHANGE_PEE,
+                Type.PUKE -> R.string.log_amount_dialog_description
+                Type.WEIGHT -> R.string.log_weight_dialog_description
+                Type.SLEEP -> R.string.log_sleep_dialog_description
                 else -> R.string.log_unknown_dialog_description
             }
         )
diff --git a/app/src/main/java/utils/NumericUtils.kt b/app/src/main/java/utils/NumericUtils.kt
index d35ae4f..6e7df67 100644
--- a/app/src/main/java/utils/NumericUtils.kt
+++ b/app/src/main/java/utils/NumericUtils.kt
@@ -66,38 +66,38 @@ class NumericUtils (val context: Context) {
         return formatEventQuantity(event.type, event.quantity)
     }
 
-    fun formatEventQuantity(type: String, quantity: Int): String {
+    fun formatEventQuantity(type: LunaEvent.Type, quantity: Int): String {
         val formatted = StringBuilder()
         if (quantity > 0) {
             formatted.append(when (type) {
-                LunaEvent.TYPE_TEMPERATURE ->
+                LunaEvent.Type.TEMPERATURE ->
                     (quantity / 10.0f).toString()
-                LunaEvent.TYPE_DIAPERCHANGE_POO,
-                LunaEvent.TYPE_DIAPERCHANGE_PEE,
-                LunaEvent.TYPE_PUKE -> {
+                LunaEvent.Type.DIAPERCHANGE_POO,
+                LunaEvent.Type.DIAPERCHANGE_PEE,
+                LunaEvent.Type.PUKE -> {
                     val array = context.resources.getStringArray(R.array.AmountLabels)
                     return array.getOrElse(quantity) {
                         Log.e("NumericUtils", "Invalid index $quantity")
                         return ""
                     }
                 }
-                LunaEvent.TYPE_SLEEP -> formatTimeDuration(context, quantity.toLong())
+                LunaEvent.Type.SLEEP -> formatTimeDuration(context, quantity.toLong())
                 else -> quantity
             })
 
             formatted.append(" ")
             formatted.append(
                 when (type) {
-                    LunaEvent.TYPE_BABY_BOTTLE -> measurement_unit_liquid_base
-                    LunaEvent.TYPE_WEIGHT -> measurement_unit_weight_base
-                    LunaEvent.TYPE_MEDICINE -> measurement_unit_weight_tiny
-                    LunaEvent.TYPE_TEMPERATURE -> measurement_unit_temperature_base
+                    LunaEvent.Type.BABY_BOTTLE -> measurement_unit_liquid_base
+                    LunaEvent.Type.WEIGHT -> measurement_unit_weight_base
+                    LunaEvent.Type.MEDICINE -> measurement_unit_weight_tiny
+                    LunaEvent.Type.TEMPERATURE -> measurement_unit_temperature_base
                     else -> ""
                 }
             )
         } else {
             formatted.append(when (type) {
-                LunaEvent.TYPE_SLEEP -> "💤" // baby is sleeping
+                LunaEvent.Type.SLEEP -> "💤" // baby is sleeping
                 else -> ""
             })
         }
@@ -108,9 +108,9 @@ class NumericUtils (val context: Context) {
      * Returns a valid quantity range for the event type.
      * @return min, max, normal
      */
-    fun getValidEventQuantityRange(lunaEventType: String): Triple<Int, Int, Int>? {
+    fun getValidEventQuantityRange(lunaEventType: LunaEvent.Type): Triple<Int, Int, Int>? {
         return when (lunaEventType) {
-            LunaEvent.TYPE_TEMPERATURE -> {
+            LunaEvent.Type.TEMPERATURE -> {
                 if (isMetricSystem())
                     Triple(
                         context.resources.getInteger(R.integer.human_body_temp_min_metric),