DoublePane from 5am Code is a gloriously simple application that rearranges two selected windows to be viewed side by side, using all of the available screen real estate.
I've been doing this for years, having two main applications open, working in both at the same time. But to do this manually, I have to drag the windows around, resize and then reposition them, until they each take up half of my screen. It is a simple process, but it's a time-consuming drag (pardon the pun).
DoublePane does the resizing and rearranging for me. I only need to select a window and tell DoublePane to place it on the right or left hand side of my screen. Repeat for the second window I want to see. DoublePane is always available from the menu bar, or by user-assignable shortcut keys. You can also restore the windows to their original positions with just a click.
DoublePane is a great productivity enhancer, and it's simple to use.
DoublePane is $2.99. A demo is available.
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