MyMTN app from MTN is offering FREE 500MB data to all customers, both old and new for chatting with friends, streaming videos, making video calls and even downloading all kinds of stuff you can imagine. This is an official data promo from MTN. Therefore, you don’t need to have airtime on your account before you can get it done and it doesn’t require IMEI tweaking. All you need is to download MyMTNApp.
The new Free Data Promo from MTN works on all MTN SIMs; the main thing that may prevent you from receiving the bonus is that if you have an active subscription, so for you to be eligible use the MTN Sim that doesn’t have an active subscription.
The app that dug out the free megabytes (MyMTNApp) is just 15MB in size, so you still have up to 485MB to do petty things on the web.
How to Know Your Eligibility for this 500MB
You might get the below message if you are not eligible:
Y’ello, Your Subscription to MyApp has failed. Please retry again later.
But, if you qualify, you will receive a message like below:
Dear customer, your free 500MB data activation was Successful.
Note:The new MyMTN app can be used to purchase airtime and data bundles, monitor data usage, and pay bills. Follow the below to get the 500MB from MTN
To Get it Done
✓To download the app, simply go to play store/iTunes store.
Direct link to download MyApp for 500MB
✓ Download the MyMTN app and install it.
✓ Choose your country and insert your MTN number.
✓ They will send you an OTP code to confirm it’s you.
✓ Insert the OTP code in the form and you will see a message like Yello, You have been rewarded with 500MB free data.
✓ Simply tap click here to activate!
✓ To check your balance, dial *559*4#.
NB: The data valid for just 24hrs, so use it before MTN trash it.
Enjoy while it last.

http://chivicworld.byethost8.com/2018/08/25/get-500mb-mtn-free-data-via-mymtn-app/

You can even accumulate up to 20GB if you want to using a new trick. It works https://www.freenetng.com/2019/08/mymtnapp-data-accumulation-trick.html especially for those that want to download huge data and don't have enough money. Enjoy