How to convert a private group to a public one in Android?
When you create a group by choosing “New Group” in Settings section (according to the previous descriptions about creating a group), and add ideal contacts as the group members; because the group is restricted in members, you call it a “Private Group”.
In order to change it to public one, you should tap the group name on top of the page and see group Settings.
Then tap the three dots icon at the top-right corner of the screen and choose the second option as “Convert to Public”. Now you can see the question about your certainty in converting your group to public.
If you are sure about your decision and touch “OK”, you will be able to see a new page with a username needed for the public group. Since this is a public group and every one of iGap users- known or unknown- can join, you have to specify a username for that (the minimum characters you can use must be between 5 to 32). After typing your favorite username, you should save it and end converting.