After deciding to get back on the GTD wagon recently I opted to use Evernote (after finding that OneNote for the Mac doesn't allow custom tags). However, I've been informed by our IT support that Evernote isn't an authorised application and my choice is limited to Outlook, Microsoft Planner and Microsoft Todo. I tried using Outlook before and found it clunky and not very mobile-friendly on my other devices. So are there any guides to setting up a GTD system using either Planner or Todo? A search online left me a bit confused. Any help would be greatly appreciated.