Please see Apple's Support article: support.apple.com/en-us/HT202180#manual
Please see Google's Support article: support.google.com/googleplay/answer/113412
Updated version not showing?
It may take some hours before an update shows as available after we have announced it. At times, we do a phased roll out of updates to ensure everything is working well before making it available to all users. Phased roll-outs typically last 7 days, so please be patient if you don't see an update immediately.
If you really do like to live on the edge, and would be happy to provide feedback to us, contact us via this page about accessing beta versions of our apps!