Meta. Why was this film so lacking in Character Development and well written characters? Because in addition to the writers' general laziness, emojis are mostly one dimensional.
Why can't they just go around the apps given that Jailbreak has some kind of map. It was because they were being hunted down by bots, so taking shortcuts was the safest option.
Why was Jailbreak's voice inappropriate for her tough-girl demeanor? Because she was originally a super-girly princess. (Although admittedly, the directors likely hadn't actually thought up something that clever, it's probably just a coincidence resulting from the casting change for Jailbreak's voice.)
Assuming Alex can't empty his trash can, Akiko Glitter is essentially in a Fate Worse than Death: Going through the cycle of her dance, in the trash full of trolls, garbage, and other malicious software. Forever.
Emojis sexually reproduce. It must be exceedingly difficult for certain Emojis to have sex, especially the ones representing apathy and sadness.
We're spared any implication that Emoji reproduction works the same way as human reproduction. Whether this is better or worse depends on your imagination, making this less Nothing Is Scarier and more Nothing Is Squickier.
Every time that you take that old phone to get recycled or break it, you are committing mass murder against the sentient workers inside each of the apps. At least in this universe.
Gene had the ability to express any emotion, and yet of all the terrible things that happened to him along the journey, he only became unemotional when his crush rejected him. This suggests that he felt entitled to have her and placed way too much emotional weight on getting the girl.
As pointed out by Bobsheaux, the only situation that should require the Emojis to have the face they represent would be when they're used - and they're given a heads up before they're used. Outside of that, there's literally no reason why they should stay with the face they represent.
As many reviewers have pointed out: Alex is too nervous to talk to Addie...yet he already has her cell phone number, which he would've only gotten had he talked to her.
Though it's possible someone else passed her number onto him. Or his inability to talk to her was a more recent development, and he got her number before his attraction-induced nervousness set in.