It isn't that you cannot live for 10 years off a large chunk of change... it is that you don't know what will happen during those 10 years. If you are fully stocked up on health, disability, life, and home insurance, you are probably OK. But most people I know who are taking time off are not fully insured for all possible scenarios, with backup plans in place. So instead, they hoard their savings.

His actual income (after Apple and paying the original game creator) was $276k - which replenished the savings he had cashed-out for development time and then gave him several more years of development on sequels/prequels.

Apple only report to you the remaining 70%, so the 800k is after the 30% is deducted.

Edit: It seems the $800k includes Apple's cut. As an app developer myself, even considering that amount is torturing yourself. Apple _only_ report the remaining 70%, especially when you consider promo codes, refunds, etc... - doing a crude sales*price is somewhat inaccurate.

(Fun fact: I'm an Australian developer. Of the amount I get paid, I also need to deduct sales tax for any sales I make to Australian consumers. For a 99c app, I would make 63c for Australian sales and 70c for other countries).

What do you do with 100k of savings? What's next?

Spend it on rent. Work again when it's dwindling.

Keep saving. You probably plan on living to an old age?