Each platform has its own restrictions regarding renewals.
OverDrive (Libby app): You can renew an item within three days of the expiry date, as long as there are no holds on the title.
TumbleBook Library: No checkouts or renewals required.
CloudLibrary Express: No renewals.
CloudLibrary French eAudiobooks: No renewals.
Cantook (Canook app or Aldiko app): No renewals.
Toutapprendre: No checkouts or renewals required.
Hoopla: A renew option will appear 24 hours before a title is due on the title details page. While you do not need to redownload a title you have renewed, renewing it title will take a borrow from your monthly limit.