Circle Pay, backed by financial powerhouse Goldman Sachs and other major investors, is a Venmo competitor with a few distinguishing characteristics. Like Apple Pay and some other payment apps, it uses a messaging interface for your transactions. But unlike Venmo and most others, it does let you send money internationally, though not to as wide a selection of countries as Xoom or PayPal. Another benefit is that you don't pay any fees to have money quickly dumped into your bank account. But forget about paying in stores or on websites, or taking advantage of loyalty programs, or paying with your voice. For those features, consider apps like Apple Pay, Venmo, or Samsung Pay.

Pricing and Starting Up

Circle Pay is free on both mobile app stores, and is a reasonably small download for both Android and iOS. I installed Circle on an iPhone X ($999.00 at Verizon Wireless) and a Samsung Galaxy S6. On Android, you have to allow privacy access to your identity, contacts, SMS, photos, and camera. The setup process is very clear and well designed. You can sign up simply, using your Facebook account, or you can create an account with an email address. After this, the app asks to find your friends by accessing your Contacts. Next it asks permission to send you notifications.

For me, the next step was verifying myself by having the app send a text message from my phone to Circle. It wouldn't be of much use if you didn't connect it to your bank, which is next. You can do so by entering your Debit Card number with a keypad, but tapping a camera icon simplifies this process by letting you take a picture of the card instead. Note that Circle doesn't accept credit cards, only debit cards; this lets the service stay free, as transactions using credit cards invariably come with fees. I entered my CVV number and ZIP code, and, voilà: The app was ready to pay!

Using Circle to Pay and Request Moolah

The app's interface is pleasingly designed. It has three main modes, accessed by choices all the way at the top: Send, Messages, and Request. The first and last simply display a big numeric keypad. Messages mode is where you see your account activity and details. Five icons atop this mode—New, Banks, Transactions, Friends, and Settings—give access to everything you need. The New button just takes you to the same numeric keypad screen. The Banks choice lets you either add money to your Circle account or cash money out to your actual bank.

Unlike Venmo (Free at Apple.com) , Circle doesn't force you to add a comment for each payment, though it is an option. Like Venmo, Circle tries to gamify payments with emoji and animated GIFs in the chat interface used between you and the contact you're paying or receiving money from. It doesn't create a social network where all you friends can see your payments, as Venmo does; that could be a plus or a minus, depending on your perspective. Unlike Square, Venmo, PayPal, and Apple Pay, Circle doesn't pop up when you tell Siri to pay someone $5. You can use Face ID or Touch ID to OK payments, however.

My initial payment limit was $400 per week, which is in the ballpark of Venmo and Square Cash (Free at Apple.com) , which start you out with a limit of $300 and $250 per week, respectively. That's less than Google Pay's $10,000 weekly limit. Most payment services let you build up your limits as you continue to use them reliably, and Circle is no different. You can even request to bump up your limit in exchange for entering details such as your social security number.

One of the best things about Circle is how fast you can get money into your bank account, and with no fee. When I made a test payment, the money was in my friend's checking account within minutes. Zelle is similarly fast—unless the recipient hasn't enrolled in that service, in which case it takes 1 to 3 days. You do need to hit Cash Out with Circle to get the money into your bank account; it doesn't flow there automatically. Square Cash offers an auto-cash-out feature, but for that you'll pay a 1 percent fee. Venmo charges 25 cents for expedited money transfers to your bank.

International Payments

Circle bests many person-to-person payment apps in that it offers international payments. The company claims it doesn't mark up exchange rates, either. That's the good. The bad? It only supports two foreign currencies, Euros and British Pounds. That's a far cry from Xoom's 66 supported currencies and PayPal's 24. Xoom has the added benefit of not requiring the recipient to have a Xoom account: They can just head to a local bank and pick up cash after showing a code and an ID. Circle's advantage over the others is its lack of fees and better exchange rates.

Extra Money Features

Aside from its chat GIFs and international payments, Circle is short on extras. You won't find support for store loyalty programs like you get with LevelUp and PayPal, and you can't use it to pay in-store or online. There's no equivalent of the PayPal's Money Pools for collecting from multiple parties. Many payment apps, including Zelle, let you split a bill among multiple people, but this feature is nowhere to be found in Circle. Nor does Circle support Bitcoin, as Square Cash does, though the company is at work on another app that does: Circle Invest.

One extra goody worth mentioning is Circle's referral program. If you invite someone to sign up, you get $5 when they pay someone $25 or more. That's free money, people!

Security and Privacy

Like Apple Pay Cash, Circle requires two-factor authentication, so if you or (more importantly) someone else tries to log into your account from a new device or browser, you need to verify with a code sent to your mobile phone. The service uses two levels of AES 128-bit symmetric encryption, as well as AI techniques to suss out fishy activity. It also supports Touch ID/Face ID on the iPhone. By comparison, Venmo doesn't specify what type of encryption it uses on its security FAQ page, though it does enforce two-factor authentication when you try to sign into your account on a new device.

All services that deal in bank cards must, however, comply with PCI-DSS, a security standard used by financial institutions, so there's some level of protection there. Venmo, Square, PayPal (Free at Apple.com) , and Circle all boast a score of A+ on SSL Labs SSL/TSL test, which is based on certificate validity, protocol support, key exchange, cipher strength, and vulnerability to SSL threats like Heartbleed and Beast.

Circle or Square?

The best things about Circle Pay are that it immediately transfers money into your bank account without a fee such as Venmo and Square charge, that it can pay in Euros and Pounds without a fee, and that you get $5 for referring friends. Otherwise, there's not much to distinguish it from Venmo, Square Cash, or PayPal, and all of those offer benefits not found in Circle, like the ability to pay in stores and use loyalty programs. For a more well-rounded payment app, check out our Editors' Choice, Venmo.

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