When your kid is on an insulin pump—and also happens to believe he’s part trampoline athlete, part stuntman, and part water-spraying backyard engineer—you quickly learn how much a diabetes device can (or can’t) keep up.
A few months back, we transitioned from the Tandem t:slim X2 to the Tandem Mobi. We’d (Owen, his mom, and I) been happy with the t:slim—especially the Control-IQ algorithm—but when the opportunity came up to switch to the Mobi (thanks, Tandem Choice Program), we were intrigued by the idea of something smaller, lighter, and potentially more kid-proof. So far, the results? Pretty good, with a few caveats. Here’s my honest, parent-tested review of the Mobi, from the perspective of a dad who lives with diabetes, works in diabetes education, and has way too much trampoline footage saved on his phone.
Why We Made the Switch
The t:slim X2 worked well, but it’s not exactly designed for kids who move like caffeinated squirrels. Owen is nine (nine and three-quarters, if you ask him). He runs, jumps, slides, climbs—and in the summer, helped me devise something we lovingly call the “Water Trampoline.” It involves a trampoline, a garden hose with precision-poked holes, and enough humidity to turn the backyard into an unsanctioned theme park ride. (Add dish soap to the jumping mat? Foam party!)
We were always a bit nervous about the pump getting wet, snagged, or otherwise disrupted during the chaos. The Mobi promised flexibility—smaller size, no screen to crack, and options for clipping, pocketing, or eventually wearing with an adhesive sleeve (more on that later). So we went for it.
First Impressions
The first thing we noticed? This thing is tiny. It fits in the palm of your hand and could easily be mistaken for a remote starter—or a pager, if anyone still remembers those.
That small size means options. We’ve clipped it to a waistband, slid it into cargo shorts, and even tucked it inside a sock once when the rest of his outfit left no viable options. (Not recommending the sock solution—just confirming that it’s possible.)
We haven’t tried the adhesive sleeve yet—which would let us stick the pump directly to his body like a tubed patch pump—but that’s next on our list. I’ll report back after a few rounds on the high-speed water trampoline.
The Pros
1. It’s discreet and lightweight.
For a ten-year-old who doesn’t love his pump being “a thing,” this is a win. No screen, no bulky rectangle—just a small device that’s easy to hide.
2.Control-IQ still does its thing.
The Mobi uses the same Control-IQ algorithm as the t:slim X2, which we’ve trusted for a long time. It predicts highs and lows and adjusts insulin accordingly. We didn’t have to sacrifice performance for size. And unlike the pumps I used “back in the day,” the Mobi updates regularly—no more being stuck on the same software for four years.
3.It can be fully controlled from an iPhone.
This is great—especially as a parent. Using the Tandem app, we can bolus, review history, and manage everything from a smartphone. It’s not just convenient; it feels empowering for Owen as he starts to take more ownership of his care.
4.It charges wirelessly.
I was skeptical, but the inductive charging pad works great. It’s like charging a phone—no ports, no fuss. We’ve made it part of the bedtime routine. Bonus: we can charge his iPhone and his pump on the same pad (not simultaneously, of course).
The Cons
1.It’s iPhone-only—for now.
That’s fine for us—we’re an iPhone family—but there’s no Android support yet. And since Owen doesn’t have a phone, I handle most of the app interactions. The physical Quick Bolus button is there, but it’s limited.
Also, the iPhone can be a hassle. The pump is small, but the phone is big for a ten-year-old. I’ve had to drive back to school more than once because he forgot it at home.
2.The reservoir is smaller.
It holds 200 units—same as the t:slim—which is fine for now (he uses ~25 units a day). But with growth spurts and pre-teen appetites on the horizon, that may change. Not a dealbreaker, but we’ll need to stay ahead on refills.
3.Charging logistics.
Wireless charging is cool, but you can’t use the pump while it’s charging. We try to charge during baths (which, let’s be honest, don’t happen daily—single dad, three kids). Traveling also means bringing the charging pad—another thing to remember in the diabetes go-bag.
Still to be decided
We have yet to try the adhesive sleeve. We’re hopeful this will make the Mobi even more patch-like, but haven’t tried it yet. I’m curious how well it’ll hold up to Owen’s water trampoline days. I’ll keep you posted.
Parent-to-Parent Tips
If you are considering the Mobi for your child
- Start slow with wear options. Test placement around the house before school or sports.
- Create a charging habit. Bedtime works for us.
- Let your child help. The app can be a great way to build early independence—even without carrying a phone.
- Stock up on adhesive aids. Skin Tac, overpatches, or the upcoming sleeve might help on high-motion days.
Final Thoughts
The Tandem Mobi feels like a big step forward for active kids who need a pump that moves with them. Is it perfect? No. But it’s flexible, reliable, and gives us more options than the t:slim did—especially for a kid who lives in constant motion.
We’re excited to try the adhesive sleeve this summer and see how it holds up. Even without it, though, the Mobi has made diabetes just a bit more manageable during school, sports, and play—especially the kind of play that involves water hoses and dish soap.
In the end, it’s still diabetes. It still requires planning, patience, and backup snacks hidden in the weirdest corners of my car. But the Mobi has made one part of that equation smaller, sleeker, and a little bit easier.
And with any luck, the only thing flying off the trampoline this summer will be shoes—not pumps.
Wait! Before you go! There are plenty of great reviews on the web. Check out these excellent reviews: