Tandem mobi -- no screen thoughts

I’m at the end of my Tandem t:slim X2 warranty and I’m thinking of replacing it with the Mobi. The thing that holds me back is the lack of a screen. I carry my iphone with me everywhere so it shouldn’t be a problem 98% of the time, but I worry about that last 2%. What if I have some sort of glitch with bluetooth or with my phone losing its charge or with a problem with the app (as just happened with t:connect)? Tandem explained that I could transfer the control of the Mobi from my phone to (for example) my wife’s phone and still be able to control my pump, but I’m not always with my wife. What if this happens while I’m on a flight or something? I’m really uncomfortable with the idea of being in the dark about what’s going on with my pump.
I guess I’ve already made my decision (sticking with t:slim because of the screen), but I’m curious what others think. Am I missing something here? Phones and apps don’t just seem quite reliable enough for the sole control of an insulin pump.

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Today At&T lost the service to a large number of there customers.

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I agree with your uneasiness of only having one device/display to control the Mobi pump. I’ve used insulin pumps for a long time but I’ve never used a system split in two like a Mobi.

I have both a spare pump and long-acting insulin to back up main pump.

You could start to carry some long-acting insulin as a back-up if you lose your phone. Switching quickly to MDI covers the need. Or you could carry a cheaper phone as a back-up. Seems like all of the back-up options detract from the whole Mobi appeal.

When I bought my last phone, I bought the insurance that replaces the phone if lost or stolen. My phone runs the app that manages my pump and CGM info. When it comes to my diabetes tech, I like to have a plan B and plan C!


I’m dying to get my Mobi, except Tandem can’t figure out how to bill my weird insurance so I’ve been given 3 different possible dates. It was supposed to ship last week, but now I have to wait for either the April or June groups.

I really feel like this is everything I want in a pump. Smaller, feather light, tubed so I can tuck it away wherever convenient and have infusion set options, waterproof (rated the same as Omnipod, 8 feet deep for 2 hours), and no more micro-USB. I’m team Android and even bought myself a cheap iPhone just to use as a remote control for it until they launch Android compatibility next year.

I know I’m cool with screenless because I really loved DIY looping, which was completely dependent on the phone at all times. I just didn’t love the Omnipods themselves. Tubed pumps work so much better for me. So I feel like this combines the best of Omnipod and T:slim info one perfect little package.

Mobi doesn’t even rely on the phone constantly, like DIY looping did. All the automation and pump settings live on the pump itself, not the phone, so Control-IQ continues to run when you’re away from the phone. You can also bolus direct from the pump without your phone, using the same exact quick bolus feature that’s on the T:slim.

You need the phone for less common tasks, like initiating an extended bolus, starting a new sensor, loading insulin, changing settings…

Also, the manual clearly states that you don’t need Internet connection/phone service to operate the pump. So it doesn’t matter if there’s a cell service issue.

The Tandem Mobi system does not rely upon Wi-Fi or cellular service to function. However, Internet connectivity is recommended for optimal use of the system, allowing for consistent wireless uploading of data to the Tandem cloud. Wi-Fi or cellular services are required to receive software updates to the mobile application or Tandem Mobi pump

I do still have 2 questions/concerns, and they’ve got nothing to with being screenlesd. Rather, they’re based entirely on the fact that I don’t plan on carrying the iPhone around everywhere. It’s probably going to live in the kitchen:

  1. You can snooze alerts on the pump, but the max setting for that is only 30 minutes. I’m not sure yet how annoying that might be. I wish they could be cleared completely. It might turn out to not be an issue, though, since BG alerts can be disabled or set to never repeat.

  2. I actually use the extended bolus option a lot. I never give more than 5 units at once, and extended the rest over like 15 minutes, or however short the pump will allow. I don’t even know if this is necessary, but I HAD to do it with Omnipod to avoid tunneling and I’ve just kept up the habit. I mostly only eat at home anyway, so I don’t think it’ll be a big issue, but I might need to set up a timer to remind me to take the second half of my bolus when I’m away from the iPhone.


You make a lot of great points, Robyn. I’m especially struck by the fact that this is far from unprecedented with people DIY looping having much greater reliance on their phones.
The fact that the Mobi keeps on running Control-IQ when it’s not connected to the phone is part of what freaks me out. I love to check stuff – did it give me an automated bolus? Did it increase the basal rate? Which personal profile am I using? Did I turn Exercise mode on? Should I cancel that extended bolus I initiated? What was my last bolus, again-- all this futzing is probably unnecessary and more of a security blanket but I don’t like the idea of being cut off from it – however rarely that would actually happen in practice.
I’m about to give the Omnipod a trial (once I finally get training) and I guess the bottom line for me will be how useful I find alternative infusion sites.

Thank you for your comments. I am finally looking at a pump and the Mobi because of all the reasons you talk about. Your comments are very helpful to me

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I’d be less concerned about iPhone reliability than Tandem’s software developers.

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Might be a good time to sell some!! Stock up 15% on friday.

I have no plans for Mobi, having used Medtronic pump for 25+ years, now on year 3.5 with Tandem X2, and Medicare in a few months.

Don’t know if it’s significant for you, but you don’t need an “unlimited” cellular data plan for the Tandem uploads (or for much of anything other than watching video on cell data) and you could cut that $25 down to closer to $15.

I’m in a similar boat. I live in the middle of nowhere and don’t stray far from home often. I don’t have a landline anymore, so cell phone is pretty important for me. I’ve done Red Pocket for years. I buy the annual plan that costs $99, or $8.25/mo. It works out to $106 after tax. No hidden fees. It comes every month with 1000 minutes of talk time (which is actually unlimited with voice over Internet calling), unlimited texts, and 1 GB of data, which is just enough to keep me entertained on the occasional trip to civilization or home Internet outage. I like that you can pick whatever cellular network you want to use, too. Our best option has changed a few times as they build new dueling cell towers. The only thing I miss from the more expensive brand name service is visual voicemail, but you can add that on for a few extra dollars a month.

I’m assuming you have other internet access since you’re online. Or are you using the phone for Internet at home, too?

I’ve never wasted cellular data on uploading to T:connect, as that happens over Wi-Fi when I want it. Honestly, I don’t use the T:connect app often, though. I have to intentionally install it again when I want to look at reports. I find it pretty useless/annoying as it currently is. I don’t like having to clear alarms in two different places.

It’s also why I wanted to make sure internet verification wasn’t required to interact with the Mobi, since I have no intention of hooking the iPhone up to our home network nor purchasing a SIM card for it

Have you pondered why the Mobi causes you to feel concerned when the Omnipod does not?

There’s no commitment with the Omnipod now that it’s billed as pharmacy. If I were signing up to use the Omnipod for the next four years (as I would be if I got a Mobi), I’d be plenty worried.
As things stand, I can try the Omnipod and go back to my t-slim if I’m traveling or doing anything out of the ordinary.

With t-slim the phone is totally superfluous (as you point out) and all pump functions can be controlled with the pump. With the mobi, the phone is an essential part of knowing and adjusting what the pump is doing. It’s the idea of control IQ running with no visibility and limited control if the phone were out of commission that bothers me — not the fact that it works without the phone per se.

Tandem has a 90 day return window on their pumps. Returns do require a doctors note. Starting the Omnipod you should be getting the starter kit that comes with the PDM which is the same multiyear commitment that you are worried about with the Tandem pumps. But don’t worry about that, both pump manufacturers have experience working with insurance companies.

If not having a dedicated screen is an issue for you it can be overcome by getting an iphone and using it only for the pump and your dexcom. Never buy a cell plan for it, never browse the web, never check your email, etc on it. The battery will last for days with nothing to do other than talk to your pump and CGM.

Pump choice is personal, get what works for you. I’m not trying to change your mind. I do hope I can help you find what really matters to you in choosing a pump.

I don’t believe that Omnipod brings any multiyear commitment with or without the PDM starter kit, best to check with your insurance. Insulet will handle insurance benefit check for you if needed.

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You’re right, John. There’s no commitment. I have a free starter kit (including the PDM) and am just waiting for training.

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It’s the Dexcom integration and the screen that makes me so happy with the X2. Having to have my phone or some other PDA with me 24/7 is a deal breaker in terms of the OmniPod. I can closely monitor things just by looking at my pump. Admittedly, my being averse to relying on my phone is due to my work history. Long before smart phones were consumer goods, I was on call throughout many nights - we had smart phones before the rest of the world. It was a short leash, and often yanked. I am happiest when my pho9ne is at home charging and I’m not!

I also like tubed pups because, as an example, if a site goes wonky, I can easily just change the infusion set and not have to deal with wasting a full cartridge (or the effort of sucking the insulin out for a replacement cartridge.
My main complaint about the X2 is the talk about Tandem getting rid of BIQ. CIQ isn’t aggressive enough for me. The target of 110 bg is too high, I would lose access to temp bolus. I am hoping to put off switching to the G7 until it too is compatible with BIQ. I like my narrow range, and rarely (maybe once a month?) get above 160 - so the CIQ automated bolus is of no value to me.
But in response to the original question of the screen - I would miss it very much.


I believe the G7 update for the X2 gets rid of BIQ. At some point the X2 will be put out to pasture. Hopefully, not soon.

I don’t plan on getting the Mobi. I do like the screen and just don’t mind pull out my pump. Also, I like the micro-pump cartridge technology better than the syringe cartridges.

I was really psyched for phone bolusing. In fact, I got my S21 Ultra specifically for that. But I found I didn’t use it. It is just as easy to pull out my pump. Moreover, I found the alerts/alarms too intrusive. I had less control over them on the phone than on the pump. And for every event, I had to deal with both. I think I will wait until Tandem makes an app that is compelling enough to give up the screen.

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I already did the “switch” from x2 to mobi. I’m happy with it. Actually I was thinking I needed full control over the phone and I finally have achieved that full control.

First of all once you program the pump over the tandem mobi app (currently only iPhone) there’s a physical quick bolus button that you can program it through the app also. Everything else in ciq is working even when your phone is not with you. There are even two LED lights on the pump.

Is very small and light, remember if you encounter any problem you can always swipe the app to close and reopen it. The connection is via Bluetooth for control of your pump. Pump and cgm (only dexcom g6 now, later g7 and freestyle libre 3 will be integrated) has direct Bluetooth for the closed loop in ciq.

Since the pump is much smaller, you have a much smaller internal battery as well, daily battery usage is around 20-25%. Charging is only through its charging pad and it’s charging quick.

The best part is the adhesive sleeves that are optional (comes 2 of them for free with the pump on initial purchase for you to try out). The sleeves that can hold the pump attached to anywhere you attach on your body is a simple and comfortable way of carrying the pump. If you still want to clip it as you used to with x2, the carry clip on case comes as an accessory as well.

Not to mention this pump is certified for ipx 28 (8 feet in water up to 2 hrs), I suppose I should be able to swim with it or shower (I did not test it though, I still disconnect from my pump during showers).

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