Automated Insulin Delivery (AID) Interoperability

Introduction to Automated Insulin Delivery (AID) Interoperability

AID interoperability is the reason a glucose sensor from one company can steer an insulin pump built by another. It rests on three FDA device types, created in 2018 and 2019, that split an automated insulin delivery (AID) system into a sensor, a pump and an algorithm the agency reviews separately [1][2][3]. As of October 2026, each sensor-and-pump pairing still sets its own rules: which phones work, how long a new sensor takes to warm up, and what the system does when glucose data stops arriving.

Three FDA categories and when each began

Each category began when the FDA granted a De Novo request for one product and wrote a new regulation around it [1][2][3]. Later products are cleared by showing they fit; the twiist pump's June 2026 clearance, for example, states that it meets every special control in the ACE pump regulation [4].

iCGM: the sensor (March 2018)

The FDA created the integrated continuous glucose monitoring (iCGM) category on March 27, 2018, when it granted Dexcom's request for the Dexcom G6 [1]. The regulation describes a sensor that measures glucose continuously and is designed to "reliably and securely transmit" its readings to digitally connected devices, including automated insulin dosing systems [5]. The G6 is now a legacy product: Dexcom stopped manufacturing it after July 1, 2026, and points users to the Dexcom G7 or G7 15 Day [6].

ACE pump: the pump (February 2019)

Less than a year later, on February 14, 2019, Tandem's t:slim X2 insulin pump with interoperable technology became the first alternate controller enabled (ACE) pump [2]. In the FDA's definition, an ACE pump is built to communicate with external devices, such as automated dosing software, so that delivery commands can be received, executed and confirmed [7]. Put simply, the pump agrees to take instructions from software it didn't ship with.

iAGC: the algorithm (December 2019)

The last piece arrived on December 13, 2019. That day the FDA granted Tandem's request for Control-IQ technology and created the interoperable automated glycemic controller (iAGC) category [3]. The agency's decision memo describes Control-IQ as software-only: it is installed on a compatible ACE pump, uses readings from a compatible iCGM to predict glucose 30 minutes ahead, and adjusts or suspends basal insulin every 5 minutes [8]. Tandem's current version is Control-IQ+, which now runs the t:slim X2 [9]. (Our AID algorithms article covers how these predictions work.)

Here's what surprised us: one category covers algorithms that live in very different places. In the FDA's January 23, 2023 clearance of Tidepool Loop, Control-IQ is described as running only on Tandem's pump, while Tidepool Loop is an iPhone app, cleared for iOS 15 or later, meant to command any ACE pump that meets its specifications [10]. Clearance isn't availability, and we did not confirm that Tidepool Loop can be downloaded in the US as of October 2026.

Which sensors drive which pumps, as of October 2026

Omnipod 5

Insulet's algorithm, SmartAdjust technology, resides on the Pod and the Omnipod 5 app. Sensor readings travel to the Pod over Bluetooth Low Energy (BLE), a low-power radio link [11]. Insulet lists the Dexcom G7 for ages 2 and up, the Dexcom G7 15 Day for ages 18 and up, and the FreeStyle Libre 3 Plus and Libre 2 Plus sensors [12]. Omnipod 5 will keep supporting the Dexcom G6 for as long as that sensor remains available [13].

Tandem t:slim X2 and Tandem Mobi

Tandem says both of its pumps now pair with the Dexcom G7 15 Day [9]. Abbott lists the t:slim X2 among the pumps that connect with the FreeStyle Libre 3 Plus [14]. The Mobi runs Control-IQ+ too, and Tandem notes something we didn't expect: its pump talks to the G7 sensor directly, not through the Dexcom app or an Apple Watch [15].

iLet Bionic Pancreas

Abbott also lists Beta Bionics' iLet as compatible with the FreeStyle Libre 3 Plus [14]; Beta Bionics' own website refused our request, so we couldn't check its full sensor list. The iLet's software stands apart. Per the FDA summary, it needs no insulin-dose settings from the user or provider and gives meal insulin in response to a meal announcement [16].

twiist AID System

twiist lists two sensors: the FreeStyle Libre 3 Plus and the implantable Eversense 365 [17]. The FDA's 2026 summary places the iAGC inside the pump itself, with the twiist app acting as the main user interface [4].

MiniMed 780G

Medtronic began the US launch of the MiniMed 780G with the Instinct sensor, made by Abbott and designed exclusively for MiniMed systems, on December 2, 2025 [18]. The FDA cleared the 780G pump as an ACE pump in July 2025 [19] and its SmartGuard algorithm as an iAGC in August 2025 [20]. So MiniMed's system now sits inside the same three categories, even though its Abbott-made sensor works only with MiniMed pumps.

Warm-up and signal loss

The first gap in glucose data comes right after a new sensor goes in. Dexcom lists a 30-minute warm-up for the G7 and 60 minutes for the G7 15 Day [21]. The FreeStyle Libre 3 Plus needs 60 minutes, per twiist [17]. MiniMed lists one hour for the Instinct sensor and two hours for Simplera Sync [22]. The implanted Eversense 365 is the outlier, with a 24-hour warm-up followed by a phase of fingerstick calibrations [23].

Only some FDA summaries spell out how a system handles these gaps. Omnipod 5 switches to a state called Automated: Limited during sensor warm-up and whenever it has gone 20 minutes or more without sensor data. In that state it delivers no more than the preprogrammed basal insulin, then returns to full automation once a valid reading arrives [11]. The iLet has a BG-run mode for when the sensor stops sending data: it keeps delivering basal insulin based on past needs and accepts fingerstick readings in place of sensor values, and the FDA summary says the mode should be used for the shortest time possible [16].

We didn't find the equivalent behavior for Control-IQ+ or twiist in the FDA summaries we read, so each system's user guide is the place to check. How to cover those gaps is a decision to make with your care team.

Phones became part of the device

With Omnipod 5, you choose between Insulet's provided Controller and a personal smartphone, and that choice limits your sensors. As of October 2026, the Controller supports all four sensors on Insulet's list, the Android app leaves out the Libre 2 Plus, and the iPhone app works only with Dexcom sensors [13]. Insulet's Android list names only Samsung and Google Pixel models, and Insulet warns that Android's Deliver Quietly setting silences every Omnipod 5 alert [13].

Tandem's t:slim mobile app runs on Apple and Android phones [9], though only on compatible models and operating systems [15].

twiist shows how fast this changes. The version the FDA cleared in April 2025 ran its app on iOS only; a June 17, 2026 clearance added an Android version without changing the pump or its algorithm [4]. In October 2026, twiist's own page still listed only iPhone and Apple Watch [17].

MiniMed ties the Instinct sensor to its phone app: the MiniMed Mobile app is required to pair the 780G pump with Instinct, so you need a compatible phone, or MiniMed's App Manager device, to use that sensor at all [24].

So a sensor on a pump maker's list isn't guaranteed to work with every controller for that pump, and Insulet notes that sensors require a separate prescription [13].