Think in regulate all with contracts.
If you got funds (kickstarter/private), or substantial money in my country and i think in europe in general, and you haven’t a company all money its considered benefits and taxes are big (around 50% passing certain amount > 2000€/3000€).
You must create a company for pay salary, expenses (software,hardware, etc) and not pay taxes for that incoming since this are not benefits. And taxes are around 20% after deduct expenses, instead of 50%.
Of course i speaking about my country but if you live in europe i think its very similar.
Do it without company or without declare the money for pay taxes and perhaps later in a year or two you receive a penalty for defraud and letter for pay “50% of all incoming”.