Default [Q] Garmin Fenix

Hi guys, with new firmware for Garmin Fenix GPS watch, i can connect my LG G2 to Fenix witch no problems over bluetooth 4 LE. Please some more experienced dev, tell me some hints if its possible to write some app for use smartwatch functions like notifications etc. At now Fenix works like smartwatch, shows notifications etc. but only witch iphone. I want to write some app but dont want to loose time if its not possible and somebody can tell me it.

Edit: Simply ma question is. Is it such easy like i can use android bluetooth api, few lines of code, or is there some bigger magic?