Alpha Testing was a period of time from January to August 2015 in which Litozinnamon charged an initial fee of 100 Robux (which decreased to 75, then became free permanently in its later life and renamed to Demo) to play the game. Before paid access, Lito would open the game for a short time and then close it again after having tested the game in its current state with other players.
The first tests conducted that were available to the public were on a modified Nuketown map. The only gun available was the M4 carbine, using an older model that does not look similar to the M4 in-game today. Bullets left long grey trails, and characters would oftentimes be unable to vault correctly. The player GUI resembled more of Call of Duty: Ghosts rather than Battlefield 3, as it currently does. This was soon changed.
Eventually the then-unnamed Crane Site map was introduced, (which has been relatively unchanged since its initial release) also featuring a small and simple click-button-for-gun loadout. Primary weapons available were the Sideways Sten (no longer in the game,) M4, AUG A1, AUG A3, SCAR-L, MP5K, Intervention, AS VAL, G36C, L115A3 (basically the AWM, re-added in the CTE and now in the actual game), SCAR-H (with a completely different sound), M60, and the UMP 45. Sidearms included the M9, M1911 (re-added in the official release), Glock 17, Glock 18, MP412 REX, and the Desert Eagle .44. There was also a truncated shotgun called the Serbu Super-Shorty, which could be taken as either a primary or secondary and was re-added as only a secondary. The only mode was Team Deathmatch, with no time or kill limit. The Phantoms were green, while the Ghosts were red. A player had an infinite grenade stockpile.
At some point during these updates, a fragmentation system for the terrain was added. This inclusion only lasted for a short time, and was eventually removed. Players could take advantage of this to hide in the storage towers and shoot out with impunity, or break into the stairwell of the parking garage.
After a few patches, the Sideways Sten was removed.
Eventually a new map appeared - Ravod 911. Once again, this map remains relatively unchanged even to this date. Ravod 911's tallest rooftops were accessible by a ladder, leading to a swarm of sniper campers who often completely broke the round until they got bored and left. These towers are now inaccessible save for glitching on top of them. Multiple weapons were introduced about the same time - the MP7, Remington 870, AK-12, AN-94, C7A2 (which is where the sights came from), G36, M16A4, M16A3, FAMAS, BFG 50 (called the Serbu BFG-50), VSS Vintorez (with a scope similar to the one on the Dragunov SVU, which was added later on to the CTE and then the main game), Dragunov SVU itself and the MK-11.
After that, the game did not get any major updates. Soon it became free, using a new framework, and the game became in open beta. This new framework required a full reworking of all weapons to use it, and greatly reduced the number of weapons available in-game. They are being slowly re-introduced over time as Shaylan remodels each one. However, re-adding the old Alpha weapons now seems to be a low priority.
Phantom Forces Demo testing was a phase in which the creator, Litozinnamon, tested his CSG guns, models and scripts.
Demo Testing began in December of 2014. It was very basic and featured around 15 weapons without customization. By Christmas of 2014 Lito had changed it to where a player had to pay 75 Robux to gain access (paid access). This period of "pay-to-play" is known as Alpha Testing. By August of 2015 Lito switched it back to where anyone could join for free. After around two months, Lito decided to move on to Beta Testing and closed the place on September the 23rd.
During the first month of demo testing, weapons were lacking and there was only a single map. After Alpha Testing was over, weapons were beginning to be better scripted with new key elements such as attachments being added. Lito had also expanded the map selection to 3.
Phantom Forces moved on to Beta, which is the version that contributed much to the game's development. In the Beta, the Developers prioritized on adding more content instead of improving or tweaking the framework, which was mostly done in Alpha. Players that had participated in Alpha Testing received the in-game title in chat of "Alpha Tester".
On the 8th of December, 2016. The long anticipated UI update was finally released, and the game went out of beta. The UI update however, was received rather poorly due to many bugs, skin lag, the Rogue-One promotion event, the Base Luna map, and a few other reasons. Overtime however, many bugs have been fixed. Recently, Alpha Testers had their Alpha Tester tag changed to "Vet", which is in bright red text.