Quick meaning
A feature in apps that reinstates paid content or subscriptions on a new device.
Think of it like this
Like presenting a receipt to claim goods you have already paid for.
Where you may see this
You may see this inside app stores, app settings, software updates, and install instructions.
Why it matters
Knowing the term helps you understand what an app is asking you to do before you tap, install, or change anything.
Say it simply
Restore Purchases means: A feature in apps that reinstates paid content or subscriptions on a new device.