So I submitted a support request regarding this issue. The response was less than inspiring!
In response to my query about the .tiff images not rendering in the iOS v. 10.0.1: "We haven’t built this feature into the new Evernote app. This is one of a handful of features we are still considering. Thanks for letting us know this feature is important to you." So I countered with: "one must ask WHY this feature was not built into the new app in the first place?? In the meantime, what am I supposed to do with all my notes containing these images?"
The answer I received is absolutely confounding:
"We haven’t yet built this feature into the new Evernote app. This feature is on our to-do list and we plan on building it soon. As far as .tiff files go we support attaching the file, but we do not support displaying .tiff file image within the note. It will display as an attachment instead. You can, however, right-click the .tiff attachment file, select open with and view it in an external image viewer as a workaround. You can also download the image locally and try converting these images to .png or .jpeg image files and you should be able to use them properly with Evernote."
Now I am really annoyed. We are talking the iOS version of Evernote here! Even as a “workaround”, how I am supposed to “right-click the .tiff attachment file, select open with and view it in an external image viewer” on my iPad or iPhone (we are talking touchscreens here and not mouse-operated computers)??? And why should I, as a premium, paying user, be required to repurpose my images as png or jpegs in order to view them again, when I could view them perfectly well in the previous version of the app?? This is not merely an inconvenience, but a truly retrograde step! How do we access the previous version of the app, and if we can’t, why are we paying premium prices for something that is no longer usable?