I'll be swamped with work when I return
This might be true. However, unless you're planning on making this a true workcation, then there's very little you'll be able to get done from your phone. So constantly looking at, or even responding to messages, won't actually get you ahead — rather, it'll just stress you out when you see what's waiting for you.
Still, I'd prefer to know what's waiting for me
Sure, I hear you on that. As someone who makes Saturday-morning checklists that involve the most minute details, I love to know what's coming up. But instead of using your inbox as some kind of impromptu to-do list, consider spending 20 to 30 minutes before you leave creating an actual rundown of everything you already know you have coming up. While things will certainly be added while you're out, odds are this'll give you a pretty good idea of what those first few days back will look like.
What if someone needs something from me and I hold them up by not responding, resulting in my co-worker getting fired?
This one has an easy fix. First, message your most reliable teammates (or boss or direct reports), and see if they can pitch in while you're out. Next, make a list of anyone you regularly work with and shoot them an email letting them know the dates you'll be unreachable; ask if there's anything you can do in advance.
Then, a few days before you leave, you can send that same email as a reminder. But in this second one, you're going to add a few lines: I won't be checking my work email while I'm gone. You can reach out to Karen for any client requests, and Dave for any design needs. If it's an emergency that requires my attention, please text me.
This does two things: Gives you peace of mind that you won't destroy someone's career while you're gone, and makes your colleagues think twice about whether something's an emergency. There's just something a little more intimate about texting a co-worker that makes you ask yourself, "Is this a real emergency, or is the kitchen being out of Diet Coke not a legit crisis?"
(Also, important note: This whole texting strategy depends on your phone plan if you're traveling internationally.)
I feel guilty asking people to help me while I sit on a beach
Assuming you're asking your teammates to simply cover for you (and not do your entire 40-hour-a-week job), you shouldn't feel guilty. This is part of working with others! This week, Karen handles your clients for you. Next week, Karen goes camping and you handle her emergencies.
(If that Karen example didn't do the trick, a small gift for those who chipped in never hurts.)