Create minimalist writing/sketching station
The lack of a windowing system on iOS and Android can be a burden for serious work, but sometimes a break from multitasking can help you focus. Grab a cheap Bluetooth keyboard if you want, and dedicate a spot in your office for writing without distractions. A good note-taking app that syncs online, such as Evernote or the Android-only Google Keep, is especially useful, since whatever you write will be waiting for you when you get back to your computer.
Of course, a text editor isn't the only tool you could have at your disposal. You could also install a diagram app, such as Lucidchart or Idea Sketch, or grab a pressure-sensitive stylus for free-form sketching.
The advantage of repurposing an older device is that you can completely dedicate it to the task. There's nothing stopping you from using a brand-new phone or tablet for any of these purposes, however. Check out PCWorld's guide to 13 highly productive Android apps that play nice with your PC.
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