Send a message direct without adding to your contact list
Fill in the phone number you want to send a message to in international form e.g. +1 650 555 7475 and press the button of the service you want to use.
Tap and add to homescreen to install this service as a web app
Sometimes you want to sent a message without going to the trouble of adding someone to your contacts. Or you don't want to bloat your contacts list with everyone you ever have sent a message. This service is for you: gotext.us lets you send a messages on WhatsApp, Signal or old fashioned SMS (or iMessage if you send from Apple to Apple device) to unkown contacts.