In iGap through Android version you have this possibility t have channels in types of public or private, even though you are able to convert your channels. Converting channels helps you have different communities, and by public one the users can join themselves easily.
Android version of iGap has a feature to create channels in private or public. You can create channels and add members or they join themselves in order to benefit the shared media by you. It helps you to share any files or news you like to with anyone whether you wanted to add or s/he added by the link.