Wahoo TICKR FIT Heart Rate Monitor

This Wahoo heart rate monitor is built on the latest optical sensors for measuring heart rates. The device is worn on the arm and is compatible with GPS watches, tablets, smartphones, multiple fitness apps and other Wahoo products. Synchronization is seamless and the battery can last up to thirty hours on active usage.

Pros
Wider compatibility
Bluetooth
IPX7 waterproof
GPS support

Cons
No display, so needs a compatible device to view results