Look at enough photos of Ibiza day parties and you could easily pack a swimsuit for the wrong one. There’s a pool in the pictures of Ushuaïa. There’s a pool in the pictures of Ibiza Rocks. If a friend sent me one photo of each and asked which we should book, I’d have a question for them first. Are you actually hoping to get in the water?

That sounds like a tiny detail until four people have paid for what they think is the same afternoon. One has a particular DJ they’ve wanted to see for years. Another has pictured a swim, something to eat and a few hours of music. I can see the appeal of both. For a first trip with one day to spare, here’s how I’d choose.

I’d book Ushuaïa for the name on the lineup

If someone in the group sends a track and says, “This one. I want to hear this one there,” my vote goes to Ushuaïa on a date that artist is playing. It’s an open-air venue in Playa d’en Bossa, with a large stage and a dance floor outside. The pool is prominent in the venue photographs, but the detail I’d pay attention to is where everybody is looking. The stage gives the afternoon a centre of gravity.

There’s a photographic reason I like that setup, too. In daylight you can expose for the sky and let the people nearest you fall into silhouette. I’d be more interested in a frame from a little way back, with the booth small and the scale of the crowd visible, than in a phone zoom of somebody behind a laptop. Once I had that picture, I’d happily move to wherever my friends wanted to dance.

The practical bit that would change my booking is the entry time. Ushuaïa sells some tickets with an earlier entry deadline. I’d take that option if we were going straight there. If the plan starts with “we’ll have lunch somewhere first,” I’d read the cutoff again before buying four of them. And I’d put the confirmation where whoever bought the tickets can find it. If you run into trouble buying tickets, Ushuaïa says to contact Clubtickets.

I’d pick Ibiza Rocks for the friend who asked about swimming

At Ibiza Rocks in San Antonio, a day pass includes use of the pool. You can go even if you’re staying elsewhere, and you can buy the pass without reserving a bed or a table. Of all the booking details I looked at, that’s the one I’d want somebody to tell me in plain English before our group started dividing the cost of a daybed nobody had actually asked for.

I’d also spend a minute on the programme. Ibiza Rocks distinguishes between headline pool parties and poolside sessions with resident DJs. Its music descriptions are specific enough to help: an R&B and hip-hop afternoon is quite a different proposition from house and disco. “Pool party” tells you what to put in your bag. The music listing tells you which friend to invite.

Of the two, this would be my pick for a first visit with a group that hasn’t settled on an artist. I like an afternoon where one person can go for a swim, two can carry on talking and everyone can come back together when a familiar song comes on. And if I were already staying at Ibiza Rocks Hotel, I’d check my room booking before buying anything else. The hotel says Pool Club entry is included for its guests.

The camera decision I’d make before leaving the room

This is where I’d change my usual travel routine. On a walk, I like having a camera over my shoulder even if I barely use it. At Ushuaïa, the venue’s policy allows personal photos on a smartphone and rules out professional cameras, telephoto-equipped digital cameras and tripods, among other kit. It also says there’s no cloakroom or locker service. Finding that out in the queue with a camera bag would be a fairly miserable start to the afternoon.

I’d leave the kit where I’m staying. And if photography were a big part of the trip, I’d give it its own bit of time before heading out. An hour with a camera and nowhere to be sounds much better to me than spending the first half of a set trying to coax a sharp frame out of a phone at full zoom.

By a pool, the decision is more ordinary. Who’s looking after the phones while everyone swims? I’d much rather sort that out over breakfast than stand at the water’s edge holding four phones and somebody’s sunglasses. I’d also ask before taking a close-up of a friend in swimwear. The pool might be the reason they picked the place. That doesn’t mean they want a picture of themselves in it.

What I’d put in the group chat

I’d send two lines. “Ushuaïa if we’re picking the date around a DJ. Ibiza Rocks if we’re picking a day to swim and hang out.” Then I’d ask everyone to send back the one thing they’d be disappointed to miss.

My own answer would usually be the pool afternoon. Give me a few hours outside, people I like and music I can dip in and out of, and I’m quite happy. But if a friend came back with the name of the artist whose mixes had been playing in our kitchen all winter, I’d change my vote. Hearing the first few bars of that track together is a pretty good reason to leave the swimsuit at home.