I currently use the G7 and Mobi pump and would like to understand more about looping and the various apps that support it. Can someone explain the benefits to me given what I am currently using? About 8-10 years ago, when I was using MDI and G4, I did use XDrip for a while on my android phone. So I understood the benefits then. But I am not sure what they would be now.
Any info is greatly appreciated. Thanks
So you are already familiar with the Tandem Control IQ closed-loop algorithm.
Looping is just another way of doing that, but it gives you more control over what settings you want.
With Control IQ, I think you can only set a target of 120 or 150, or something like that, right? Looping lets you set whatever target you want.
Similar to the way Tandem works, you set your basal rates and BG targets. But you can set them for whatever you want.
When you are in closed-loop, the app will give you more or less basal depending on what your CGM number is. And it will also give you micro-boluses if your BG is high enough.
If you switch it to open-loop, it just follows your pre-programmed basal rates. It does not make any changes if you are in open-loop.
Advantages:
You have one less device to carry. It all runs on your phone, and most people always have their phone with them anyway. You donât need to carry a pump around. (Although with the Mobi, itâs kind of the same thing there, since Mobi runs from your phone.)
The other advantage is that you have total control over the settings. Your BG target can be anything you want.
Disadvantages:
You have to use Omnipod Dash. I think Dash is fine, but if you are not used to it, it might be an adjustment to switch to it.
You have to build it yourself. It takes some time to learn how to build it. Itâs not too hard, but just takes patience and reading. And you can ask people here for help.
Thanks Eric. Arenât there other open source options that do not require switching to Omnipod Dash?
Can you clarify this? I thought the pump and phone always have to be close to each other.
If you are talking about looping in terms of a commercial pump, all 3 of the big pump manufacturers now do this - Medtronic, Tandem, and Insulet (OmniPod). There is also iLet, which is not one of the big 3, but they also do it.
If you are talking about a do-it-yourself loop system, you can do this with either iPhone or Android. There is code available that allows you to do it with either type of phone.
But you need a pump to go with the do-it-yourself loop system. As far as I know, the only pumps that work with this are OmniPod Dash, and very old discontinued versions of the Medtronic. You might still be able to find one of those Medtronic pumps, but itâs not easy because they have not been made in quite some time.
Unless there is some other option I am not aware of, I think those are the only 2 options. 
Someone please let me know if I am missing something on this.
@funk It has gotten to the point there is not an easy answer to your question, because the environment of âloopingâ (small âlâ) has become diverse. It depends largely on what phone/OS you have and what country youâre in to determine what pumps and CGMs are available and what AIDs work with them. @Eric has provided a good basic review of Tandem and commented on Dash pods; Dash pods are the favorite for looping software because the security of the pumps BT signal is known, yet considered relatively secure. In the US, the primary platforms for looping (small l) using DIY apps are Loop (large âLâ, V3.6 just came out, requires iPhone/iOS), AAPS (not sure of current version, requires an Android phone), Trio (currently in beta testing w/a small group, public beta due out soon, its an offshoot of iAPS, requires iPhone/iOS), and iAPS (not sure of current version, changes more frequently than most, I believe still requires iPhone/iOS). Most DIY iAIDs are compatible with a varying set of iCGMs (most support Dexcom G6/7, many support Libre 2/3, several others are supported dependent on the iAID software); some are compatible with varying pumps (Dash is the primary for Loop, Trio, and iAPS [I canât speak to AAPS as Iâm not sure). Commercial pumps state they are âloopable,â but true capabilities vary depending on your definition of âloop.â Some allow a BG range higher than many people want, some allow a limited correction factor, some are a âblack boxâ (i.e. you donât know what the algorithm is); the list goes on. In addition, some are available via âpharmacyâ benefit channels (current Dash pods are one), some only via DME (Durable Medical Equipment) channels (Tandem and Medtronic are examples). If you live outside the US, the number of available pumps, their manufacturer iAIDs, compatibility with DIY iAIDs, and compatibility with iCGMs varies even more.
On the good side, the options available for iAID software, iCGMs, and pumps is growing. It seems some pump manufacturers have broken the code that people expect pumps to work with multiple CGMs and AIDs, vice stove-piped into manufacturer vertical monopolies. Example the new Twiist pump, using a commercial version of the Loop code, is due out by EOY 2025 and is supposedly going to be compatible with both the Dexcom G7 and Eversense 1-Year, possibly the Libre 3. On the DIY AID side, the community has long sense broken that code and has expanded software to be compatible with multiple CGMs and pumps for some time and itâs growing to support more.
The best advice is to do your own search. Check what pumps are approved for use in your country, then check what AID software will support those pumps (commercial or DIY) and what CGMs are readable by the AID software. The one differentiating item is what support there is for the combinations available to you and what are your abilities to handle the combinations. Is DIY a realistic option for you? Is commercial and hands-off what you need/want? Itâs not quite the defined commercial environment it once was, and the DIY environment isnât quite the Wild West it once was either. We can be thankful the #WEARENOTWAITING folks pushed both the commercial and DIY markets!
Tom and Eric
Thanks so much for all this info/feedback. I think I am going to have to sit down with a glass of wine tonight and read thru all of this very carefully. There is a lot out there and I hadnât realized I was asking such a loaded question.
Thanks again and I may be back with more questions!!
Any questions you have are welcome! FYI, Iâve used Loop, iAPS, and Trio. Iâm currently a beta tester for Trio. Iâve used both Apple Xcode and Browser Builds for each (it takes time the first time and ability to carefully follow directions); subsequent browser building is easy. Thereâs plenty of help available on FB, GitHub, or Discord. Iâm not a programmer and it doesnât take one to do it. There is a cost: you need an Apple developer account, $90/year. I have not used a commercial AID/looping system or tubed pump (Dash was my first and only). I should have included that Loop (I think Trio and iAPS too) can use older Medtronic pumps (pumps may be out of warranty), not sure if newer variety will work with it/them. Some people swear by commercial systems (like Omnipod 5), others swear at them. YDMV is the catch phrase. Hope your research takes you in the right direction for you!
Newer Medtronic pumps do not work. The older ones that do work are hard to find now. They are highly sought after online because they allow looping.
If you find one of the older compatible Medtronic pumps being sold online, it would go for an exorbitant price. I think they were the Medtronic MiniMed 515 and 522, and a few other old Medtronic models. I donât recall all the numbers.
Trio also supports the Dana RS/-i pump.
While AndroidAPS supports a number of other pumps besides Dash, Medtronic and Dana pumps.. I believe it also supports Medtrum, Tandem t:slim and Ypso pumps.
Is it available in the U.S. now? For a while I think it was only available in Europe. I did not know if that had changed.
Trio, Loop and AndroidAPS all support Dana RS / i pumps. I believe Dana i pump is FDA approved.
From Diabetech posted in 2022:
Thanks @Trying. Yes, thatâs 
what I saw which I was referring to.
Basically, it would work if you can get one, but it was not widely distributed yet in the U.S.
But that was a few years ago, so it might be easier now.
Yes, there are users but Iâm not sure who is in the US. I just know that the developer is very responsive in integrating it with Trio and other loop AID systems.
I, too, use the Mobi and Dexcom G7. The only difference I see at this point between DIY looping and Mobi/G7 system is that with looping you can set your BG target to whatever you want, and on the Mobi, 110 is the lowest BG target allowed. The other settings on the Mobi are very flexible. The big caveat is knowing how to use the settings to your best advantage. Sigh. That is the crux of the matter. For me, at least, it will be a lifetime of trial-and-error and tweaking. My endo thinks Iâm fine at A1c 6.4, TIR 92 and standard deviation of 31. Itâs that standard deviation that I wish I could settle down, but my lifestyle is such that itâs hard to get better numbers. If DIY looping is really different from Mobi/G7 system, other than BG target options, someone please let me know! My personal experience with the Mobi/G7 is that I work just as hard at managing my BG now as in the days before smart algorithms, but with the Mobi/G7 I am more successful.
I havenât used Mobi, so let me just ask a few questions to point out flexibilities that I have with DIY Loop.
On the Mobi, do you just enter grams of carb, or can you inform the algorithm that itâs 16g of carb in glucose tabs, or 16g of carbs in peanut butter? Because they are not the same, and if the algorithm doesnât know how fast your carbs are, how can it do the right thing?
On the Mobi, can you say you plan to eat 100g carb in the form of pizza an hour from now so that it can start prebolusing as needed?
On the Mobi, if you took a bolus for an estimated 30g carbs, and then a half hour later you notice that your BG is rising faster than it should, can you go back and inform the algorithm that it really must have been 45g carbs so the algorithm should adjust the dosing to compensate? Thatâs different from entering another 15g of fake carbs now, because the dosing is already running behind the insulin requirement.
Suppose you had to pull an all-nighter, so the next day youâre a bit more resistant to insulin. Can you tell the Mobi algorithm that you need an extra 20% insulin today? Not just a basal adjustment, but also for meal boluses, corrections, and everything.
I think thereâs lots of useful control in DIY Loop. For me, itâs more of a cooperative activity, rather than having the algorithm try to do everything itâs own way with maybe some work-arounds that I can use to trick it, such as by lying about my basal requirements or carb intake.
Thanks for your questions! No, Mobi certainly does not help in any of these ways you have itemized and I struggle with each of these scenarios! So, how do you âinform the algorithmâ of these situations with DIY loop?
Here is a screen shot with tandem ctrl-IQ settings (same for Mobi and t-slim). There is also a new feature to make a temp basal rate while still in ctr-IQ, but the temp rate gets superseded by crtl-IQ so I am not yet understanding it.
This is really the same with looping too though. Crap in crap out is real no matter what method you employ. If you donât know what ISF and Basal rates are, for instance, or how to test, adjust and look for patterns that need addressed, youâre always going to be dissatisfied and lacking the desired control.
The first three questions I posed have to do with food and adjusting the algorithmâs response.
The meal entry screen has 4 fields
If you donât enter anything other than the grams of carb, it just acts like a traditional pump, so you arenât required to use all the fancy features and answer lots of questions with lots of button presses. For example, if I just want to eat a 50g sandwich, I type the following:
press the "meal" button
50
press the "continue" button [it shows the recommended bolus which you can change]
press the "save and deliver" button
That was 5 button presses. On my old t:slim it was something like 14 button presses to get it done.
If you notice that your BG is rising too fast or is topping out too soon, suggesting that the meal bolus wasnât right, itâs possible to change what you originally entered. Loop saves the data for all of todayâs meals in a table. The meal grams, time eaten, and absorption time are stored as a line in that table. Itâs easy to tap on a line to bring up the food entry screen pre-filled with the numbers from the table, but you can edit any of them, for example to change the grams, or the absorption time, or even the eating time. As before, the continue button goes to the bolus amount screen, which will show any additional bolus that the algorithm suggests based on the new information and the amount of insulin and remaining carbs in your system. As always, you can accept the suggestion or change it to whatever you want. And it shows a graph of your estimated BG over the next 5 hours based on all the food and insulin the algorithm knows about, so you will see if it thinks you already have too much insulin and maybe should consider eating some extra carbs to avoid going low.
If dealing with extra insulin resistance or insulin sensitivity, you press the âcustom presetâ button. This is a bit like âexercise modeâ on a traditional pump, but much more adjustable. Here thereâs a slider showing overall insulin needs, pre-set to 100%, but you can adjust it anywhere from 10% of normal to 200% of normal. There are also fields for target BG range in case you want your BG to run higher (or lower) than usual; start time; and duration of this override (in 15 minute intervals for up to a day, or âenable indefinitelyâ if you donât know how long it will take for your insulin sensitivity to return to normal.
You set the kind of insulin in DIY Loop because the algorithm uses the actual published insulin absorption curves for Humalog, Novolog, Apidra, Fiasp, and Lyumjev. This enables the algorithm to be more accurate than it would be if it just used a âduration of insulin actionâ setting like the 2 or 3 hours that we used to put into traditional pumps to try to get them to dose more aggressively.
If you take a manual bolus by syringe or by Afrezza inhaler, thereâs a screen to enter that information so that the algorithm can take that into account when deciding itâs automatic insulin corrections every 5 minutes.
Can I adopt you? (Just kidding; I have enough adopted children.) Thank you! This is the best description of loop that I have seen. Food for thought, for sure! I might have to check it out again - Facebook, right?