Below is a list of sites, programs and apps you can use absolutely free to earn various cryptocurrencies. These can either be held, staked for extra passive income, or converted into your local currency (usually for a small fee deducted from the transaction itself).
I have included in this list every free platform for passive cryptocurrency income that I have found, in no particular order. Proofs of payment can be found on the "Verification" page. Though I'm going to say this again for each applicable listing, UNDER NO CIRCUMSTANCES SHOULD YOU INVEST MONEY INTO ANY LISTING THAT HAS NOT BEEN CONFIRMED TO PAY OUT AS PROMISED!
Free Chrome clone with cloud mining incorporated
CryptoTab Browser is a clone of Google Chrome available for Windows and Android with one notable extra feature: it uses your device's spare processing power to mine Monero and convert it into Bitcoin as long as the mining tab is open in the browser. That means that, simply by leaving the browser open, your device mines cryptocurrency for you without costing extra electricity or battery power or having to install complicated hardware and program workers to mine specific pools. If you have no idea what any of that means, that's fine. All you need is a Bitcoin wallet, several of which can be found on the Asset Storage page. Download and install the browser, register an account, and let CryptoTab do all the work while you surf the web! One account can be used for as many devices as you have and all of them will mine for you as long as CryptoTab is open. Android users should be aware that the free version of CryptoTab requires you to use the browser for 10 days before you can begin mining and, because mobile devices typically have much lower processing power than PCs, the mining hashrate will be very low. However, this can be offset by referring users through your personal link (you earn a percentage of their mining which is not deducted from their earnings, so everyone wins) and/or investing in CloudBoost (I did this and do not recommend it, as even at 10x hashrate a phone just doesn't have the power to make the investment profitable in a reasonable amount of time without multiple high-end devices mining together).
The thing that makes CryptoTab Browser truly shine is the TEN-LEVEL referral system. Yes, you get paid a percentage of the earnings of your referrals, their referrals, the referrals of their referrals on down ten levels deep. That's a serious pyramid, but this one doesn't require anyone to buy in, so go forth recruiting without worrying whether you're screwing your family and friends.
Update: CryptoTab just released a new feature called Super.Boost, which allows users on mobile devices using CryptoTab Pro to further enhance their CloudBoosted hashrate by up to 400%. If you combine this with the ability to run multiple instances of Nox with CryptoTab Pro, you can dramatically increase your mining speed. Super.Boost is a monthly subscription service, but I think this one is worth it if you use the Nox trick. For a demonstration and instructions, see https://www.youtube.com/watch?v=0Oivf8icfVo
Crypto-earning through publishing
Publish0x is a website which allows users to create original content, publish it on the site and earn tips from users who read, watch or listen to it. The site is in beta, so they are only allowing a limited number of authors at this time, but any user can send tips and even choose the percentage of the tip that goes to the author and the rest goes to you. The default percentage is author - 80, you - 20 and that's what I use. This is probably where I'll end up publishing the first few chapters of my book to make some pocket change and get feedback from readers.
Targeted-ad browser that blocks unwanted ads and trackers while paying users BAT for opted-in ads
Okay, I know. I've had CryptoTab Browser on here for ages and I'm just now listing Brave Browser. Well, that's because it took me a long time to figure out how to generate a referral link AND how the paid ads actually work. They show up as notifications, in case you were wondering and no, you do not have to click or otherwise interact with an ad to get paid for it. As for the referral link thing, that was a bit of a chore. You see, you have to become a Creator, which means you have to have some kind of platform for advertising Brave to the world. In my case, this involved editing the DNS record of this website with a verification TXT: a task which took me no small amount of time to remember how to do. YouTube channels work as well. Ads pay 0.1 BAT per, so it is in your best interest to set the number of ads allowed per hour to 5 (max). Unlike CryptoTab, running Brave on multiple devices will not increase your earnings. Referrals are where you will make the big bucks, if you have the social influence to get them.
If you are already a Brave user, please feel free to leave a tip!
Earn Phoneum tokens(PHT) with free cloud mining
Cloud Earning PHT is one of several partner apps available in the Play Store through which users can earn PHT for free. This one is a simple open-start-close system that mines PHT for 7 days, after which users must claim their earnings and start the mining process again. 100 PHT = ~$0.01USD and the minimum amount for withdrawal is 15000 PHT.
Crypto mining game with real profits
I'm not going to lie, this one is actually a lot of fun for me. You play little mini games, win hashrate, mine satoshi and expand your virtual mining enterprise. Additional assets can be deposited in order to buy mining rigs faster, or your assets can be withdrawn at a minimum threshold. There is a good chance that, between this and Coin Birds, I'm going to forfeit a lot of sleep.
Solve captchas. Get crypto. Nuff said.
Credit to Worm for her post on Publish0x for my being able to find this little gem. BTCCaptcha offers a wide variety of crypto to earn and each one requires you to solve one of three types of captcha:
Raincaptcha: ten seconds between solves, where you select the shapes being made by the funny little moving pixels
ReCaptcha: I hate me some ReCaptcha, in which you select pictures from a list or series of lists, but there is no wait between sovles
SolveMedia: my personal favorite, just type the words you see as fast as you can or select the answer to the question from a dropdown menu, with no wait between solves (I can knock out about 2000 of these per hour)
There are, of course, varying minimum withdrawal amounts from one crypto to the next. Some types can only be withdrawn to a direct wallet, but if you have an account at faucetpay.io, and you absolutely should, you can withdraw supporte crypto there at much lower minimums. So, get over to BTCCaptcha and start earning your favorite coin or token!
BEWARE THE OCCASIONAL PORN AD REDIRECT
A lot of things about this site seem weird, but after trying it for a while, I can't find any scam.
I had this up once before, then took it down at the behest of another user. I continued to test the site on my own, however, and after more than a month I have not found any way for users to be scammed out of their own money. Nothing about Gramfree requires any invested capital. It is a bit strange to have a page dedicated to users watching videos of other users claiming the site is legit and showing payment proofs, etc. That said, if they don't require users to pay anything into the program to get something out of it, what's the scam? So, I am putting this back up. You can take a look at the site and decide for yourself, but it seems harmless to me.