‘What is this app used for?’ The answer is often misunderstood: you can open a chat on the official WhatsApp app (or Business) with another user if you know their number. This app replaces the method of saving the number into contacts. This will NOT allow you to ‘spy other conversations’, ‘contact with numbers without WhatsApp’, ‘hide your number’ or other crazy things. This is the same as clicking an unknown number on a group, creating manually the url link or saving the contact.
‘Why should I use this instead of others?’ You are free to choose of course! This app only has the ‘open in WhatsApp’ feature and improvements, but for this reason the app is extremely simple and so I made it without ads, as small a possible, and free; just to help others use this feature that WhatsApp have (note that I’m not affiliated with WhatsApp Inc). Since I published it the popularity increased as unexpected (thanks!) and other apps with the same functionality (some even blatant copies without my permission) have populated the store. You can use whichever you prefer, but this one is (last time I checked at least) the smallest of all, the only one add-free, and the only one without ‘dangerous’ permissions (not internet, not storage, nothing. Check it! ).
This app uses WhatsApp ‘click to chat’ feature (https://faq.whatsapp.com/en/android/26000030/) to open a chat with any number (a chat between you and that number).
No contact is created on the device, you don’t need to save it on your contacts list. Just open the app, enter the number, click the button and the chat will open (if the number doesn’t exists WhatsApp will notify it).