Steg is a simple handy app that allows you to send files through WhatsApp, popular messaging platform. It allows you to seamlessly send files relevant to your chat that's unsupported by WhatsApp without the hassle of you going out of your way and using e-mail or Drive, etc. For example another app you wish to show a friend or a zip file. It can also be used as a way to get around WhatsApp's image compression when it distorts your photos. Or to send an avi video. Whatever the file type, be it binary or text. Just make sure both parties have Steg installed. And whatever you want to share via WhatsApp, share with Steg instead. This gives you an Encode Activity that's already autofilled the input. Just click Encode and Share Encoded File and then use WhatsApp to share. Really simple.
On the other device the person receives what you sent and all he has to do is click on it from WhatsApp, select Steg to open it, click on Decode file and then Open Decoded File. That's it. Really nothing to it.