diff --git a/.idea/compiler.xml b/.idea/compiler.xml
index fb7f4a8..61a9130 100644
--- a/.idea/compiler.xml
+++ b/.idea/compiler.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="CompilerConfiguration">
-    <bytecodeTargetLevel target="11" />
+    <bytecodeTargetLevel target="1.8" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index 561b289..dd95f50 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -18,5 +18,5 @@
     </option>
   </component>
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="11" project-jdk-type="JavaSDK" />
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" project-jdk-name="11" project-jdk-type="JavaSDK" />
 </project>
\ No newline at end of file
diff --git a/app/release/output-metadata.json b/app/release/output-metadata.json
index fb95255..948c000 100644
--- a/app/release/output-metadata.json
+++ b/app/release/output-metadata.json
@@ -10,8 +10,8 @@
     {
       "type": "SINGLE",
       "filters": [],
-      "versionCode": 2,
-      "versionName": "0.2",
+      "versionCode": 3,
+      "versionName": "0.3.1",
       "outputFile": "app-release.apk"
     }
   ]
diff --git a/app/src/main/java/it/danieleverducci/nextcloudmaps/utils/Color.java b/app/src/main/java/it/danieleverducci/nextcloudmaps/utils/Color.java
new file mode 100644
index 0000000..f92fc48
--- /dev/null
+++ b/app/src/main/java/it/danieleverducci/nextcloudmaps/utils/Color.java
@@ -0,0 +1,22 @@
+package it.danieleverducci.nextcloudmaps.utils;
+
+public class Color {
+
+    /**
+     * Based on Nextcloud Maps's getLetterColor util
+     * @see "https://github.com/nextcloud/maps/blob/master/src/utils.js"
+     * @param catName category name
+     */
+    public static generareCategoryColor(String catName) {
+        // If category is default, return default color
+
+        // Else
+        int letter1Index = letter1.toLowerCase().charCodeAt(0);
+        int letter2Index = letter2.toLowerCase().charCodeAt(0);
+        var letterCoef = ((letter1Index * letter2Index) % 100) / 100;
+        var h = letterCoef * 360;
+        var s = 75 + letterCoef * 10;
+        var l = 50 + letterCoef * 10;
+        return {h: Math.round(h), s: Math.round(s), l: Math.round(l)};
+    }
+}