Thanks for using Zoom SDK. Regarding your questions:
1. Can Zoom provide a notification sound (like a “beep” sound) alert at a designated time - e.g. every 2 minutes and 30 seconds for both the host and participant (to notify ending time of the call)?
You could set a timer to achieve this after you have successfully started/joined the meeting. If you would like to get notified when the 40 minutes free meeting is ending, you may use this callback:https://zoom.github.io/zoom-sdk-android/us/zoom/sdk/MeetingActivity.html#handleConfPayReminder-boolean-
2. Can Zoom provide recording services of our 1:1 calls (both video and audio) into a file where we can have access to the recorded files for either download or streaming services?
Our Android SDK supports cloud recording, you may use the method in https://zoom.github.io/zoom-sdk-android/us/zoom/sdk/InMeetingCloudRecordController.html to use the cloud recording feature.
3. Can a user record a video of himself/herself, not of a video conference call?
Unfortunately, this is not supported.
4. Does Zoom provide a function where we can overlay texts on the streaming video view?
You might consider Custom UI feature:https://marketplace.zoom.us/docs/sdk/native-sdks/android/mastering-zoom-sdk/in-meeting-function/customized-meeting-ui/overview. If you would like to get the video data, inject the text into the video stream and then render it. We do not support that at the moment.
Hope this helps. Thanks!