The Seeed T1000-E is by far the best hiking companion. It’s water and dust-proof, has a 2+ day battery life, and excellent range in credit-card form factor. Plus it looks nothing like a radio so it won’t attract suspicion from certain groups.

The format is called RTTTL

Yup! Under the External Notification config menu there’s a section to program the piezo buzzer tone/delay sequence. I changed mine to be more of a chirp than a full ringtone.

I do like the ringtone. But I think what’s even cooler is the ability to set your own ringtone through the config.