Game developer Pasha Zinchenko on the main game forum (https://vk.com/club90031290) has shared link for open Beta testing, pre-release & for users that do not wish to use the Google Play store (There is currently no info if the iOS/Steam version will receive this type of attention in a near future)
Currently the preferred download link for LATEST Version is his Dropbox but as of 03/26/2017 the Event Horizon site include an early release link
https://www.dropbox.com/s/mssi7b1q1rxio43/eventhorizon.apk?dl=0
Notes/Points of interest
- Early/Beta releases tend to have BUGS which can cause save game to be lost, caution is advise and its recommended you perform a cloud save to reduce information lost
- Version is not final in any way and may present multiple changes, please do not take all "updates" as definitive to update the wikia unless they are noted as present in early release or beta release
- The piracy/cheater flags in the pre-release versions are "locked" meaning hard cheats that would enable the space invaders "mod" to occur can be performed/tested with minimal risk, again as noted above a cloud save is recommended in case of save data corruption