There is this app, Honeygain which let you earn money by sharing your unused Internet Data. You can install the app in your android phone, IOS device or Windows PC to run the program. There is nothing for you to do basically and you will earn passive money daily which you can withdraw out either to your BTC wallet or PayPal.
Below is the result that I have after testing Honeygain for the past 15 days. I only have one device that I'm using this app so my earnings will not be that fantastic. On some days, it seems good that I'm able to make $0.14 per day. However for the past 8 days, the results are not really fantastic. Yesterday only managed to get 14.47 credits even though my device was unused and left alone just to run Honeygain. My phone is not a really old phone by the way so I'm not sure what is preventing Honeygain to use more of "unused" internet data. My internet speed is reasonable fast so I'm still figuring out where the issue is that is preventing me from earning more.
As you can see from my accumulated earnings, I only have 1,449 credits. I do not have the Free 5000 Credits which is equivalent to $5.00. If you sign up with my referral link you will get a sign up bonus of 5000 free credits. As the minimum payout is only $20, you can reach very fast requiring only another $15. I would need much more than that since I did not manage to get the free credits. From the looks of it, it will take me awhile before I can reach payout. I can only expect to get some credits for the daily honey pot jar.

You should be able to have no limit to earn from this Honeygain app if you have tons of unused devices. The app only take a small amount of storage in your phone or PC. If you have Unlimited Internet Plan, you can use that since you won't be able to finish up your quota. In the settings you can configure when you wants to turn off the Data Sharing or Use Data Only On Wifi Connectivity so you can keep your limited data to yourself.
The Honeygain earning calculator estimate that to earn about $19 per month, you will need at least 3 devices install with the application. Taking $19 per month with 3 device, you will need each device to earn you about $0.21 cents per day. However based on my own test with one device, the highest I could get was only $0.14 cents per day. You may try the Honeygain app and share your results with me.

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