You can make them for links you use all the time, like for your store or website. It's a simple user-friendly interface with some bells & whistles but the basic simple-text shortcuts are insanely useful:

You can set macros, too, which I haven't messed with because frankly, I have never really understood macros. Where I just typed ' tu1' instead of searching around my computer for the image and using the camera icon to insert it in the post. You can also make a shortcut for inserting an image instead of text, like this Which I inserted here simply by typing rt - the shortcut I assigned to this sample string. There is no limit on the length of the text your shortcut can expand to, and you can do 'rich text' too which you can format for color, size, italics, bold, underline and strike-through.

It's called ' FastFox' and I am loving it. A couple of nights ago, while searching for something else, I stumbled on an app for the computer that does this. I miss this convenience terribly when I am using the computer. So for example instead of typing out my whole email addy I can just type 'em1' and it automatically becomes my full email addy. Many moons ago I installed a keyboard app on my phone that lets me set my own custom shortcuts for stuff I type a lot, like my email addy or phrases I use a lot etc.

Download fastkeys text expander