What should i learn if i want to make a meeting app

Answer 1

For iOS app developments,

https://www.sololearn.com/discuss/1932517/?ref=app
https://www.sololearn.com/discuss/140730/?ref=app

Answer 2

For Android app development,

https://www.sololearn.com/discuss/112635/?ref=app
https://www.sololearn.com/discuss/32469/?ref=app
https://www.sololearn.com/discuss/1121296/?ref=app
https://www.sololearn.com/discuss/1489928/?ref=app
https://www.sololearn.com/discuss/1077096/?ref=app