Tech Cards are bonus cards that provide additional income for the businesses or for tapping.
They are available in Card Shop for diamonds. You also get Tech Cards when you prestige or when you have sent enough soldiers for the weekly war.
xx Tech Cards are available as of version xx.xx. There are different types: normal and gold.
Here follows a list of Tech Cards
|Invis-a-wear||x1.5 Tap Profit||Stealth Clothing
When you want to see but not be seen.