We are in the process of finalizing code base separation for AppMaster Developer mobile applications for IOS and Android. Until now, you were able to preview v3 and v4 mobile applications inside Developer apps.
Starting from the next week we will publish AppMaster Developer Legacy (working title - may be corrected upon stores publication) - app dedicated to opening v3 applications only. A couple of weeks later our primary AppMaster Developer apps will open v4 apps only.
Once new applications for v3 will be available in AppStore and Play Marker we will additionally notify everyone.