I’ve written before about Hook, a nifty way of linking things you’re working on together so you can seamlessly bounce between them. I’ve thoroughly integrated it into my workflow now and adore how quickly I can jump from one document to another — in a different app, even — without ever looking away from my work. It helps me reach and maintain a state of flow.

Hook depends on an app’s ability to support deep linking to its contents. Many apps are helpful, like OmniFocus. It supports both a right-click “Copy as Link” action to all sorts of items, and allowing other apps to ask it for a link to its currently selected item. Consequently, Hook’s OmniFocus support is top-tier, and I can make links between a to-do item and the website that documents how to do it. Other apps are less helpful, like Apple’s own Reminders app which supports neither users nor other apps asking for a direct link to an item. It somewhat supports drag-and-drop linking to other apps, but that’s not nearly so convenient and powerful as OmniFocus’s methods.

Apps should be more like OmniFocus than Reminders. To that end, Hook’s author Luc P. Beaudoin collaborated with an all-star list of Apple software developers to write the Manifesto for Ubiquitous Linking, which says in part:

We affirm that the ability to copy a link to a resource is as important for cognitive productivity as the ability to copy other types of information. This applies to all persistent digital information.

We invite software developers to do their part, by

  1. ensuring their users can conveniently obtain a link to the currently open or selected resource via a user interface; and
  2. providing an application programming interface (API) to obtain or construct a link to that resource (i.e., to get its address and name).

I could not agree with this, or endorse it, more heartily. Anyone can write an app that locks away content behind its own twisty maze of navigation links. The best and most powerful applications open themselves to users. Today I can link from an OmniFocus action to a DEVONthink document, and from there to an Obsidian note, whether on my Mac or my phone or iPad. Tomorrow, I want to go directly into any of my apps. If you’re an Apple developer, please take the time to read and consider this manifesto.