I use todo.txt with topydo (https://github.com/topydo/topydo) and Todo.txt for Android (https://play.google.com/store/apps/details?id=net.c306.ttsuper). That solution works well for me.
For work stuff I use Sublime Text with PlainTasks (https://github.com/aziz/PlainTasks), but I'm not entirely happy with that solution, partly because of the file format.
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