diff --git a/app/src/main/java/io/github/sspanak/tt9/ime/helpers/AppHacks.java b/app/src/main/java/io/github/sspanak/tt9/ime/helpers/AppHacks.java
index 777f8326..ebed762d 100644
--- a/app/src/main/java/io/github/sspanak/tt9/ime/helpers/AppHacks.java
+++ b/app/src/main/java/io/github/sspanak/tt9/ime/helpers/AppHacks.java
@@ -85,6 +85,12 @@ public class AppHacks {
 	}
 
 
+	/**
+	 * Simulate the behavior of the Sonim native keyboard. In search fields with integrated lists,
+	 * ENTER is used to select an item from the list. But some of them have actionId = NEXT, instead of NONE,
+	 * which normally means "navigate to the next button or field". This hack correctly allows selection
+	 * of the item, instead of performing navigation.
+	 */
 	private boolean isSonimSearchField(int action) {
 		return
 			DeviceInfo.isSonim() &&
@@ -92,7 +98,7 @@ public class AppHacks {
 			&& (editorInfo.imeOptions & EditorInfo.IME_MASK_ACTION) == action
 			&& (
 				inputType.isText()
-				// in some apps, they forgot to set the TEXT type, but fortunately, they did set the multiline flag.
+				// in some apps, they forgot to set the TEXT type, but fortunately, they did set the NO_SUGGESTIONS flag.
 				|| ((editorInfo.inputType & EditorInfo.TYPE_TEXT_FLAG_NO_SUGGESTIONS) == EditorInfo.TYPE_TEXT_FLAG_NO_SUGGESTIONS)
 			);
 	}
@@ -139,6 +145,11 @@ public class AppHacks {
 	}
 
 
+	/**
+	 * onAction
+	 * Runs non-standard actions for certain apps and fields. Use instead of inputConnection.performEditorAction(action).
+	 * Returns "true" if the action was handled, "false" otherwise.
+	 */
 	public boolean onAction(int action) {
 		if (isSonimSearchField(action)) {
 			return sendDownUpKeyEvents(KeyEvent.KEYCODE_ENTER);
diff --git a/app/src/main/java/io/github/sspanak/tt9/ime/modes/ModePassthrough.java b/app/src/main/java/io/github/sspanak/tt9/ime/modes/ModePassthrough.java
index 593cb4fa..6af351fe 100644
--- a/app/src/main/java/io/github/sspanak/tt9/ime/modes/ModePassthrough.java
+++ b/app/src/main/java/io/github/sspanak/tt9/ime/modes/ModePassthrough.java
@@ -2,8 +2,6 @@ package io.github.sspanak.tt9.ime.modes;
 
 import androidx.annotation.NonNull;
 
-import io.github.sspanak.tt9.R;
-
 // see: InputType.isSpecialNumeric()
 public class ModePassthrough extends InputMode {
 	ModePassthrough() {
diff --git a/app/src/main/java/io/github/sspanak/tt9/preferences/items/ItemText.java b/app/src/main/java/io/github/sspanak/tt9/preferences/items/ItemText.java
index 383a435c..2c6fb640 100644
--- a/app/src/main/java/io/github/sspanak/tt9/preferences/items/ItemText.java
+++ b/app/src/main/java/io/github/sspanak/tt9/preferences/items/ItemText.java
@@ -12,7 +12,7 @@ import io.github.sspanak.tt9.preferences.PreferencesActivity;
 import io.github.sspanak.tt9.ui.UI;
 
 public class ItemText extends ItemClickable {
-	private PreferencesActivity activity;
+	private final PreferencesActivity activity;
 	public ItemText(PreferencesActivity activity, Preference preference) {
 		super(preference);
 
diff --git a/app/src/main/java/io/github/sspanak/tt9/preferences/screens/appearance/ItemStatusIcon.java b/app/src/main/java/io/github/sspanak/tt9/preferences/screens/appearance/ItemStatusIcon.java
index 17ce12f4..f0f5cf02 100644
--- a/app/src/main/java/io/github/sspanak/tt9/preferences/screens/appearance/ItemStatusIcon.java
+++ b/app/src/main/java/io/github/sspanak/tt9/preferences/screens/appearance/ItemStatusIcon.java
@@ -7,8 +7,8 @@ import io.github.sspanak.tt9.preferences.settings.SettingsStore;
 public class ItemStatusIcon {
 	public static final String NAME = "pref_status_icon";
 
-	private SwitchPreferenceCompat item;
-	private SettingsStore settings;
+	private final SwitchPreferenceCompat item;
+	private final SettingsStore settings;
 
 	public ItemStatusIcon(SwitchPreferenceCompat item, SettingsStore settings) {
 		this.item = item;
diff --git a/app/src/main/java/io/github/sspanak/tt9/ui/UI.java b/app/src/main/java/io/github/sspanak/tt9/ui/UI.java
index 69a1f677..259ec976 100644
--- a/app/src/main/java/io/github/sspanak/tt9/ui/UI.java
+++ b/app/src/main/java/io/github/sspanak/tt9/ui/UI.java
@@ -12,8 +12,6 @@ import androidx.annotation.NonNull;
 
 import java.util.HashMap;
 
-import io.github.sspanak.tt9.R;
-import io.github.sspanak.tt9.languages.Language;
 import io.github.sspanak.tt9.preferences.PreferencesActivity;
 
 public class UI {