Tokens are akin to lottery tickets or lotto chips. They are simply itmes used in game of chance (Spinning) to be used to gamble for items like Credits, Gold, Skill Cards, Boosts, Premium etc. from token chests.
It is possible for players to buy tokens for the clan account which will be distributed among all clan members based on their clan activity. Please note that a minimum of 100 tokens has to be in the Clan Account for them to be distributed.
There are several chests which can give you Tokens. They are:
Advertisement Chests
Clan Supply Chests
Contract Chests
Free Chests
Token Chests (sometimes more than you invested in the chest and sometimes less)
War Chests
It is possible to gain additional tokens for creating content based on the game. It is extremely important to realize, that this requires a lot of long term dedication though. But if you already have an Art of War 3 youtube channel, you might as well give it a try. More Information (external link)
Usually there is an event around the end of December till the beginning of January where players can get huge amounts of tokens quite easily (in the thousands).
Geargames sometimes holds competitions in their official social media. Those usually offer tokens as a reward (often in the 5 digit numbers).
Geargames regularly provides YouTubers with promo codes for tokens which they tend to give away on their youtube channels. A list of youtube channels can be found here.
Tokens are only used for opening token chests of which several types exist. Opening them gives can cost either 5, 50 or 500 tokens and more expensive chests obviously give better rewards. Some rewards like Skill Cards can even be exclusive to some token chests.
Rewards include: Blue / Red / Gold Boosts, Credits, Gold, Tokens, 1 / 3 / 7 / 12-day speed ups, Premium, Blue / Red / Purple Skill Cards, and Super Container points
The aforementioned super container points are included in every token chests and always come as a constant amount. More expensive token chests give more bonus points. These super container points can be used to open 3 different kinds of super containers when you gather enough.
There have also been events on Christmas when there was a Purple Token chest which cost 2500 tokens and gave even greater rewards, so it might be a good idea to save up tokens for future events.