Google Checkout.

Didn't it just get merged with Wallet?

https://developers.google.com/wallet/

Google Checkout had subscriptions.

Google Wallet does not have subscriptions.

Yes it does.

https://developers.google.com/wallet/digital/docs/subscripti...

Ok, it looks like subscriptions. Though it does not allow me to charge my customers who subscribed for Google Checkout. And it's definitely not the same API as Google Checkout.

None of my customers missed Google Checkout. I got burned by losing subscriptions due to Google Checkout retirement.

I'm not going to touch Google Wallet.