A guide to update angular-meteor 1.2 to 1.3 version?

I have a small app which still uses meteor 1.2 version, I’m using angular with it.

I’m having issues with the deployment in heroku of this app since the release of meteor 1.4 and I was wondering how to update it to 1.3 and eventually to 1.4 but I can’t seem to find a good guide on how to achieve this.

Any help would be appreciated.

Thanks!