That said, the Gmail mobile app recently began to support third-party email providers, so who knows--maybe Inbox will eventually follow suit.
2. There's no universal inbox
If you've got multiple Gmail accounts (I have three, for example), there's no "All inboxes" option as there is for the Gmail mobile app.
Instead, you'll need to switch back and forth (just tap the menu button in the top-left corner of the screen, then tap one of the circular icons to switch accounts).
Again, Gmail for Android recently added an "All inboxes" feature, so perhaps Inbox will too. In the meantime, though, the lack of a universal inbox is a big disappointment, especially given that the whole point of Inbox is to help us save time.
3. Inbox needs to be trained
Inbox does a pretty impressive job of sorting through your email and shuffling messages into the correct bundles, but it'll make some mistakes at first--a lot of mistakes, potentially.
That means you'll find yourself dipping into various bundles to move sorted messages from one to another--say, a shopping receipt that winds up in the "Low Priority" bundle rather than in "Purchases."
The good news is that Inbox will keep track of any messages you move so it can remember for next time. But initially, at least, all the resorting and reshuffling may feel like more of a headache than it's worth.
4. You can't mute message threads
One of my favorite Gmail features is its ability to silence--or "mute"--annoying message threads (or "conversations," as they're called in Gmail). Once you mute a thread, it'll skip your inbox until you unmute it, or if one of the participants forwards a message in the thread only to you.
It's a great feature--and sadly, one that's (for now, anyway) missing from Inbox. The ability to mute conversations may well sneak into a future version of Inbox, but for now, you'll have to tolerate all those endless "Congrats!" and "Cute baby!" threads.
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