Gem upgrades are permanent upgrades that cost gems. They are never reset. They have a linear cost increase.
The gem generator is the primary way of generating gems. It costs cash to upgrade and every purchase increases the cost. It works online and offline.
The spinner generation and max upgrade increased the cash per second and max cash capacity of spinners by 1%. The max is 100k %.
The increase online and offline earned increases your passive cash income. It works online and offline, so it's a good first upgrade to get. The max is 100%.
The spinner spawn cooldown reduces the cooldown between spinner spawns. Each level reduces the time by 0.2 seconds to a minimum of 0.5 seconds.
The bouncer collision vortex cooldown reduces the time between possible vortex spawns. Each level reduces the time by 0.2 to a minimum of 5 seconds.
The collector constant speed increased the minimum speed of the collector by 0.3 to a maximum of 30. This will keep the collector moving around, allowing it to collect from spinners without your input.
The spinner generation per gem will increase the spinner cash generation by a percent for each 200k gems earned. This will let you continue to increase your cash earned with gems. The max is 50%.