One mistake I had when implementing Auto-renewable Subscription (a kind of In-app purchase) is not understanding how the sandbox environment works.
That resulted in wasted hours in debugging..
You should know this:
Time flies much faster in sandbox than actual. So a 1 week subscription will be only 3 minutes in sandbox. This actually helps because you can test your app much faster.
|Actual duration||Sandbox duration|
|1 week||3 minutes|
|1 months||5 minutes|
|2 months||10 minutes|
|3 months||15 minutes|
|6 months||30 minutes|
|1 year||1 hour|
Also, it will automatically renew maximum 6 times.
UPDATE: WWDC 2018 seems to change to maximum 5 renewals
Here’s a screenshot right from WWDC 2018: