I am using Ionic and wrote an Angular module that makes calls to the Web API. Not too far down the road yet but I can login, get device details, read variables, call functions and subscribe to events. I have not taken on device setup as of yet which will most likely be the most difficult part but I think I can get there. I may see if the Particle team wants to take over support for the module or put it on GitHub for people to find. I can share it but will need to extract it from my code and do some cleanup prior to that so if you are interested I will need a little bit of time.
One thing to think about is that all hybrid apps like PhoneGap and Ionic can be EASILY extracted and your code viewed. Do not place anything secret in this code as it is a massive exposure. For testing I am not using two-legged auth so the clientID I am using to request tokens is well known particle:particle but in the future you will need to make allowances to retrieve you particular apps client ID and secret (OAuth creds) dynamically and use them on the fly.
I do believe you can just wrap the JS lib as well but I wanted to keep things as Ionic native as possible so wrote my own.