how can I confirm that data send on notification subscription are successfully received

[makouda]

I want to send big amount of data (10kb) with characteristic of 16 bytes. when the phone side is subscribed to notification I run a loop of data sending.

how can I synchronize data transfer with phone side? . I mean I wont send index i+1 if index if im not sure index i is successfully received

[Petter Myhre]

If you want the app on the phone to say i is successfully received, I think indications is a better option. More info here. That said, you will not lose any packets with notifications, that is, before they are given to the app. The app can ignore the notification, and the peer wouldn't know.