You already got the Apple Watch, but are intrigued at taking wearable smart technology a step further: to smart jewelry. Smart rings have been around awhile now, but are they worth it?

Here the skinny on what’s out there in the smart ring space.

1. Kerv
This NFC ring is focused only on payments and ID. It allows you to make payments, unlock smart locks and validate ID for public transport. Its Kickstarter campaign is still underway. Available in seven colors for both men and women, its goal is to make contactless payment easy and accessible.

2. Neyya
Want a Bluetooth remote control you can wear? Then check out the Neyya smart ring. It connects to your computer, GoPro or smartphone, but instead of tapping on a mouse, you tap on the ring. Great for delivering smartphone notifications.

3. Ringly
This smart ring is hugely popular with the ladies because it looks like a cool piece of jewelry rather than wearable tech. The great thing about Ringly is that you can allow or disallow what comes through: texts, emails, social media notifications or app reminders.

4. MOTA SmartRing
This smart ring has a tiny screen and vibrates when you get social alerts, emails and texts. It connects to your smartphone via Bluetooth and its screen allows you to scroll through your notifications.

These aren’t the only smart rings out there; you’ll be surprised at the actual number available (and with varying capabilities). If you want to dig into the smart ring arena a little more, check out other brands like NFC ring, Altruis, Fin Ring and Vring.