I made a simple calculator that tells you how much liquid of each type you have to use to make your own juices as all the options in the store were overloaded or had too many nasty ads. And I thought you guys might like it as well. As I do not have the necessary $25 to spare to get a developer license from Google (needed for publication in the Play store) I decided to distribute the APK freely over Google Drive: https://drive.google.com/open?id=0B5-IuyHOc1o2NlZ2bW1fX2hRX2c.

Here are 2 images to show what the app does: http://imgur.com/a/m1VqG

Note: this app is only there to quickly calculate the amounts needed for making your own juice and has no intention to be a recipe collection app, there are other apps and webpages that do this way better and I had no desire to create an overloaded recipe-collection app. The app does not have any ads or in-app purchases, however there is an option to donate hidden in the about menu (and the app will never ever bug you to do so). If I get donations I will use these towards the Google Play store developer licence and for future updates.

In general you should not trust random APKs on the internet (the same goes for any files from the internet), so please proceed with caution and use common sense (I'm not telling you how to live your life, so you're free to use common sense or not :)). I implemented this on a fresh Linux Mint using the latest Android Studio, so if in doubt, do not use this app.

Also, please let me know what you think! Happy vaping!

EDIT: Updated version available here: https://drive.google.com/open?id=0B5-IuyHOc1o2Q29ydzE4bHlwZWc With this version you can select if you have PG or VG based nicotine and/or flavours (see http://imgur.com/a/00fsm).