Jawbone's new UP4 range-topper activity tracker lets you make NFC payments

Wearables company Jawbone now has a new flagship activity tracker. Called UP4, it is the company's first offering to come with NFC payments support. Also announced is a new mid-range activity tracker, called UP2, which is touted to be an "elegant replacement" for the aging UP24.

To enable NFC payments in UP4, Jawbone has teamed up with American Express. To pay, UP4 wearers will simply have to attach their Amex card to their Jawbone account. This can be done straight from the Android or iOS mobile app.

How does it work? Well, Jawbone says that it's as straightforward as tapping your wrist on the payments terminal. A successful transaction is accompanied by a signal, to let you know that you can walk out of the store (or other places where contactless payments are supported by the vendor).

Jawbone says that the system is as secure as the one that comes with Amex cards. Also, the company claims that it "does not see" your account or payment information -- this is likely enabled by the way cards are enrolled using Jawbone's mobile apps. Jawbone also says that those who do not have Amex cards can apply for one right from its mobile apps.

Of course, that's not all that Jawbone's new UP4 can do for wearers. The activity tracker is actually based on the UP3, which only recently went on sale. The way Jawbone describes UP4, the only difference between it and UP3 seems to be the NFC payments support.

So, for more info on the new device you might as well read this article detailing UP3. The highlights are advanced activity, sleep and heart health tracking. The cost? An UP4 will set you back $199.99, when it's available this summer.

If you're not interested in making NFC payments, then UP2 might be a better fit for you. Also, if you already have an UP24 and want something smaller, then UP2 might be the natural replacement. Jawbone says that it's 45 percent smaller than the activity tracker it replaces, which is certainly good news.

I have worn an UP24 for a few good months, and found that it can be uncomfortable when resting my hand on the desk (or any flat surface, for that matter). It also slows down my typing, which means it has to come off when I need to be at the desk. Needless to say, I haven't used it recently because of it.

Without testing UP2, I can't really ascertain whether it solves this problem for me, but the smaller size is certainly promising. Thickness is said to be between 3 and 8.5 mm. Jawbone claims it's "the lightest and most discreet tracker on the wrist", which, if true, might make more consumers consider wearing activity trackers.

UP2 will not be available in multiple sizes, like UP24 is, as Jawbone has fitted it with a buckle system for a "one-size fits-all" approach. This is another interesting thing about UP2, as it makes it easy to hand over the device to, say, a friend to try for a while (or simply sell it). That is, as long as your wrist size is between 140 and 190 mm.

For notifications, of any sort, UP2 will only vibrate to let the wearer know they've achieved a goal, or when it's time to prepare for bed. It's similar to UP24; it also has that subtle led on top. That's something that hasn't proved useful in day-to-day usage of my UP24.

The battery in UP2 is rated for seven days of usage, with 100 minutes needed for a full charge. Jawbone is again using a dedicated cable for charging, and this one doesn't seem to be backwards-compatible with UP24. A replacement cable costs $9.99.

UP2 costs half as much as UP4, retailing for $99.99 on Jawbone's site. For the money you get basically the same features that you get with UP24, but in a much smaller package. That means UP2 offers activity and sleep tracking, food logging, an intelligent coach feature that gives you tips, and more. And it's available now, in black and light gray. UP24 is no longer offered.