This app was mentioned in 6 comments, with an average of 1.67 upvotes
I had the same issue with my pebble steel. I resolved it by installing the original pebble android app in addition to the new one.
https://play.google.com/store/apps/details?id=com.getpebble.android&hl=en
Install it, log in but do not pair it with the old orange pebble app just pair it with the new grey pebble app. Having android ware may also help.
https://play.google.com/store/apps/details?id=com.google.android.wearable.app&hl=en
What are you calling the last update?
So the "fix" for this in the past was that you had to install the "old" version of the Pebble app and then it magically worked. The one thing I'll tell you is that it will kill your battery having both the old and the new Pebble app installed.
I always just read the "what's new" section on the app page. This one says:
What's New
While you're using the Kindle app on iOS, there are also Kindle devices. If /u/TeamPebble could add the Pebble app to Amazon's App store, then Kindle, Fire tablet, and Fire phone owners could install it directly onto their device. At that point, developers could write apps to control the page flips on the Kindle, interact with the Kindle music player, etc.
Without the Pebble app in Amazon's store, Amazon device owners (Kindle readers, Fire tablets, & the Fire phones) are locked out of using Pebble watches with their devices.
(FYI, there are no rooting tools available for recent versions of FireOS, thus Google Play store is not available)