I recently bought the Garmin premium heart rate monitor but it won’t work with either strava or endomondo. Which HRM is best when using both apps?

What phone are you using?
The Garmin HRM uses ANT+, so you need a phone with that built in, or an ANT+ adapter.

Or get a Bluetooth heart rate strap instead.

This help?

http://getsatisfaction.com/endomondo/topics/how_do_i_setup_my_ant_heart_rate_device_garmin_fisica_wahoo_on_iphone_and_android_phones_with_ant_chip

Samsung galaxy s2

You’ll need a Bluetooth HRM, not a Garmin one.

I’ve got a Zephyr Bluetooth one – works flawlessly with Endomondo, not tried with Strava but no reason to think it wouldn’t work. Using a Galaxy S3.

Other posts are right in saying you can’t use ANT+ monitors unless you’ve got an ANT+ phone (and there’s not many of them about).