Q: how do I view purchase history on my iPhone?

Install iTunes in PC & Login From that to See Purchase History or you can see your Purchase History from iPhone AppStore also

Sorry, but a computer with iTunes is the only way to view your entire purchase history. You would sign your Apple ID into the iTunes Store, then click on Account Info. That is the only place where you can see all of your purchase history. You can also go to reportaproblem.apple.com on Safari on your device or on a computer and see the last 90 days of your purchase history.

Here is a support article that may help:

See your purchase history in the iTunes Store on a Mac or PC - Apple Support

And no you cannot view your Purchase history from the App Store on your iOS device....

Sorry,

GB

on your device, go to reportaproblem.apple.com and you can see the last 90 days worth of iTunes purchases.

Echo.....

GB