Inbox Dollars as a simple source of extra money in terms of active participation is a waste of time. It took me from 12/28/15-6/4/16 to earn $37. Anything online that is active (clicking emails, surveys, watching videos, etc) should pay you at least 10-cents per minute (The M-turk decent average, but maybe I'll explain M-turk in a futer blog post) . Clicking for the next video, emails, surveys etc is considered being active. However, outside of emails and downloading apps (1 time limit) you cannot actively earn at least 10-cents per minute.
Here are the means of my earnings:
Video earnings have a low return (10-cents for watch 100 15-30 seconds videos) for having to actively select the next video:
Videos, search, downloading apps, emails, & surveys are the primary vehicles to make money without having to sign up with an advertising partner for goods or services. However, surveys can act strange in which you could waste 10-minutes...and then are told you don't qualify for the survey. If you don't mind signing-up with different advertising partners for their goods or services it may be worth your time to earn money passively with Inbox Dollars.
The cash out minimum is $30, but there is a $3 processing fee. That fee can be waived on first cash-out if you attempt to cash-out at $30 and then inbox Dollars gives you 30 days to reach $40...and therefore you don't get hit with a processing fee. But as I said earlier, I cashed out at $37.
Anyways, once you cash out you need to remain active everyday by checking a paid email or watching a video until the check comes in the mail or a gift card is credited.
My time is better doing something else for active money. I plan to stick with Perk as a money earning app(s) as it is passive money that does not take my time away from engaging in more productive methods of earning money online.