Simple clock wallpaper with current day of week, date, WiFi network name, next alarm time, and battery status. Minimal memory and battery consumption. Background image is also customizable. More options will be added eventually without any Ads or 'premium only' version.
Note to Samsung (and some other vendors) owners: sometimes there is no option to set up a live wallpaper on the stock launcher. Please use Google Wallpapers or third party launcher to do it. See https://forums.androidcentral.com/samsung-galaxy-s7/780940-how-install-live-wallpaper-galaxy-s7.html

*OK, I was contacted by a few companies willing place the Ads in the app despite the description. There is how you do it.
You will need:
• an Android based phone;
• a pen;
• a post-it sticker note.

Please follow these steps carefully:
1. Get a pen with the right hand and a post-it sticker with the left one. You might find it more comfortable to swap hands if you are left-handed.
2. Write your Ad text on the post-it sticker using the pen.
3. Put the pen away.
4. Take a phone with a free hand.
5. Glue the post-it sticker to the phone screen.
That's all! Now you have your Ads placed! It works even when the screen is off, and you can update the ads from time to time.
Cheers!