To save you the effort of swiping your credit card (sarcasm alert!), services like Apple Pay, Google Wallet, and PayPal let you check out by using only your phone. Seriously, there are advantages to a digital wallet. Have questions? Here are answers.

By Yelena Moroz Alpert
Updated January 21, 2015
Oliver Munday

How does it work? You download an app to link your credit card to one of these systems. Then use your phone to pay at checkout terminals.

Which service is best? If you have an iPhone 6 or certain iPad models, you already have the capa­bility to use Apple Pay. There’s not much difference between Google Wallet and PayPal’s app.

Is this technology safe? Yes. It’s actually safer than a credit card. Each system has its own protective layer: Google Wallet requests a four-digit code to open the app for a fixed period of time; PayPal asks for username and password before putting through purchases; and Apple Pay relies on a passcode or fingerprint verification.

Are my purchases being tracked and my info sold to marketers? No, your shopping habits are not shared with third parties. Apple Pay doesn’t collect any transaction information; Google Wallet stores encrypted payment info but doesn’t sell it; PayPal implements cookies for ad targeting, but you can turn them off.

Can I pay by phone everywhere? Popular stores, like Whole Foods Market, Panera Bread, and Walgreens, accept Apple Pay and Google Wallet. PayPal is accepted at other merchants, like Home Depot and American Eagle Outfitters. A separate group of retailers, including Walmart, CVS, and Target, are developing their own payment app, called CurrentC. Huge growth in mobile payments is expected this year.

How will this change my life? You can pay the babysitter more easily—Google Wallet and PayPal let you send and receive money. Depending on the system, you may be able to upload gift cards or loyalty cards.

If my phone dies, am I stranded and penniless? Yup! No juice, no transaction. If you are notorious for running around with a dying phone, get a power booster. Tylt Energi Sliding Power Cases (from $80) will give you about 10 extra hours.

If I lose my phone, can a thief charge millions? No. Your credit-card numbers are encrypted in the cloud, so it’s not the same as losing a card that someone can swipe at a gas station. You can lock down everything remotely. And you won’t have to request new cards with new numbers when you replace that lost phone.