rn: add more SDK documentation

android/sdk/src/main/java/org/jitsi/meet/sdk/JitsiMeetConferenceOptions.java

      */
     private Boolean welcomePageEnabled;
 
+    /**
+     * Class used to build the immutable {@link JitsiMeetConferenceOptions} object.
+     */
     public static class Builder {
         private URL serverURL;
         private String room;
         public Builder() {
         }
 
+        /**\
+         * Sets the server URL.
+         * @param url - {@link URL} of the server where the conference should take place.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setServerURL(URL url) {
             this.serverURL = url;
 
             return this;
         }
 
+        /**
+         * Sets the room where the conference will take place.
+         * @param room - Name of the room.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setRoom(String room) {
             this.room = room;
 
             return this;
         }
 
+        /**
+         * Sets the JWT token to be used for authentication when joining a conference.
+         * @param token - The JWT token to be used for authentication.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setToken(String token) {
             this.token = token;
 
             return this;
         }
 
+        /**
+         * Sets the color scheme override so the app is themed. See:
+         * https://github.com/jitsi/jitsi-meet/blob/master/react/features/base/color-scheme/defaultScheme.js
+         * for the structure.
+         * @param colorScheme - A color scheme to be applied to the app.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setColorScheme(Bundle colorScheme) {
             this.colorScheme = colorScheme;
 
             return this;
         }
 
+        /**
+         * Indicates the conference will be joined with the microphone muted.
+         * @param muted - Muted indication.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setAudioMuted(boolean muted) {
             this.audioMuted = muted;
 
             return this;
         }
 
+        /**
+         * Indicates the conference will be joined in audio-only mode. In this mode no video is
+         * sent or received.
+         * @param audioOnly - Audio-mode indicator.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setAudioOnly(boolean audioOnly) {
             this.audioOnly = audioOnly;
 
             return this;
         }
-
+        /**
+         * Indicates the conference will be joined with the camera muted.
+         * @param videoMuted - Muted indication.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setVideoMuted(boolean videoMuted) {
             this.videoMuted = videoMuted;
 
             return this;
         }
 
+        /**
+         * Sets the welcome page enabled / disabled. The welcome page lists recent meetings and
+         * calendar appointments and it's meant to be used by standalone applications. Defaults to
+         * false.
+         * @param enabled - Whether the welcome page should be enabled or not.
+         * @return - The {@link Builder} object itself so the method calls can be chained.
+         */
         public Builder setWelcomePageEnabled(boolean enabled) {
             this.welcomePageEnabled = enabled;
 
             return this;
         }
 
+        /**
+         * Builds the immutable {@link JitsiMeetConferenceOptions} object with the configuration
+         * that this {@link Builder} instance specified.
+         * @return - The built {@link JitsiMeetConferenceOptions} object.
+         */
         public JitsiMeetConferenceOptions build() {
             JitsiMeetConferenceOptions options = new JitsiMeetConferenceOptions();
 

android/sdk/src/main/java/org/jitsi/meet/sdk/JitsiMeetView.java

     }
 
     /**
-     * Joins the conference specified by the given {@link JitsiMeetConferenceOptions}.
+     * Joins the conference specified by the given {@link JitsiMeetConferenceOptions}. If there is
+     * already an active conference, it will be left and the new one will be joined.
      * @param options - Description of what conference must be joined and what options will be used
      *                when doing so.
      */

android/sdk/src/main/java/org/jitsi/meet/sdk/JitsiMeetViewListener.java

      *
      * @param data Map with an "error" key with the error and a "url" key with
      * the conference URL. If the conference finished gracefully no `error`
-     * key will be present.
+     * key will be present. The possible values for "error" are described here:
+     * https://github.com/jitsi/lib-jitsi-meet/blob/master/JitsiConnectionErrors.js
+     * https://github.com/jitsi/lib-jitsi-meet/blob/master/JitsiConferenceErrors.js
      */
     void onConferenceTerminated(Map<String, Object> data);
 

ios/sdk/src/JitsiMeetConferenceOptions.h

 
 @interface JitsiMeetConferenceOptionsBuilder : NSObject
 
+/**
+ * Server where the conference should take place.
+ */
 @property (nonatomic, copy, nullable) NSURL *serverURL;
+/**
+ * Room name.
+ */
 @property (nonatomic, copy, nullable) NSString *room;
+/**
+ * JWT token used for authentication.
+ */
 @property (nonatomic, copy, nullable) NSString *token;
 
+/**
+ * Color scheme override, see:
+ * https://github.com/jitsi/jitsi-meet/blob/master/react/features/base/color-scheme/defaultScheme.js
+ */
 @property (nonatomic, copy, nullable) NSDictionary *colorScheme;
 
+/**
+ * Set to YES to join the conference with audio / video muted or to start in audio
+ * only mode respectively.
+ */
 @property (nonatomic) BOOL audioOnly;
 @property (nonatomic) BOOL audioMuted;
 @property (nonatomic) BOOL videoMuted;
 
+/**
+ * Set to YES to enable the welcome page. Typically SDK users won't need this enabled
+ * since the host application decides which meeting to join.
+ */
 @property (nonatomic) BOOL welcomePageEnabled;
 
 @end

ios/sdk/src/JitsiMeetView.h

 
 /**
  * Joins the conference specified by the given options. The gievn options will
- * be merged with the defaultConferenceOptions (if set) in JitsiMeet.
+ * be merged with the defaultConferenceOptions (if set) in JitsiMeet. If there
+ * is an already active conference it will be automatically left prior to
+ * joining the new one.
  */
 - (void)join:(JitsiMeetConferenceOptions *)options;
 /**

ios/sdk/src/JitsiMeetViewDelegate.h

  *
  * The `data` dictionary contains an `error` key with the error and a `url` key
  * with the conference URL. If the conference finished gracefully no `error`
- * key will be present.
+ * key will be present. The possible values for "error" are described here:
+ * https://github.com/jitsi/lib-jitsi-meet/blob/master/JitsiConnectionErrors.js
+ * https://github.com/jitsi/lib-jitsi-meet/blob/master/JitsiConferenceErrors.js
  */
 - (void)conferenceTerminated:(NSDictionary *)data;