Google Pay is described as 'is the fast, simple way to pay with Google online, in stores, and more. Book a trip, grab a meal, see a show, and enjoy new experiences—all without your wallet. Just add a card once from a participating bank and you’re ready to go' and is a payment processing service in the business & commerce category. There are more than 10 alternatives to Google Pay for a variety of platforms, including Android, iPhone, Online / Web-based, Windows and Mac. The best alternative is PayPal. It's not free, so if you're looking for a free alternative, you could try Litecoin or Bitcoin Cash. Other great apps like Google Pay are Taler, Apple Wallet, Payoneer and DASH.
GNU Taler is a privacy-preserving payment system. Customers can stay anonymous, but merchants can not hide their income through payments with GNU Taler. This helps to avoid tax evasion and money laundering.
Wallet keeps things like airline boarding passes, movie tickets, and gift cards all in one place, letting you scan your iPhone or iPod touch to check in for a flight, get into a movie, redeem a coupon, and more. Wallet is what you would use to set up Apple Pay.
Lydia is a mobile payment solution. Started with payment through QR code, email or SMS and direct money exchange with friends using your credit card, it is now an all-in-one payment and money management service.
If you want to sell digital content online, there's plenty of options out there. However, if you want to sell digital content online without violating your users' privacy in the process, you'll have a much harder time finding a suitable program.