Tandem Mobi (pump)

The Tandem Mobi is a miniature durable automated insulin delivery system — a small pump less than half the size of the t:slim X2 that can slip into the coin pocket of a pair of jeans or be worn in an adhesive sleeve.⁸⁹ It is a tubed pump, not a patch, but it shrinks the tubed format dramatically: the small durable pump body connects to the body through a short, detachable infusion set (including a 5-inch tubing option), so you can briefly disconnect to shower or swim.⁹

Reservoir and wear. The Mobi uses a clear ~200-unit insulin cartridge, smaller than the t:slim X2's ~300-unit cartridge, which is the trade-off for its size.⁸⁹ The cartridge is paired with standard Tandem infusion sets, so the site/cannula is changed every 2–3 days following standard pump practice.⁹ The pump body itself is durable, rechargeable by wireless (inductive) charging, and rated IP28 water-resistant (up to 8 feet for 2 hours).¹⁰

Infusion set and occlusion detection. Because it is compatible with the full Tandem infusion-set range, users can mix and match cannula type, angle, and tubing length.⁹¹⁰ Like other Tandem pumps, it includes occlusion (blockage) detection and alarms; as with any infusion-set pump, a kinked or bent cannula may not always trigger an alarm immediately, so site rotation and glucose monitoring still matter.¹¹

Recall — "Malfunction 12". The Mobi carries an FDA Class 1 recall (recall number Z-0427-2026, the FDA's most serious category, covering 17,745 units in commerce). A software-design fault could make the pump falsely detect a vibration-motor failure and raise "Malfunction 12": the pump then cannot operate, insulin delivery and any active CGM session stop, and the phone app can no longer receive data from the pump — which can lead to hyperglycemia and, untreated, to DKA.¹ Only software versions 7.6.0.1, 7.6.0.3 and 7.7.0.1 are affected; for this Malfunction 12 issue specifically, an update to 7.9.0.2 or later is the fix. It does not resolve every other open Mobi correction. This is a correction, not a removal — the pumps stay on the market.¹

Two other open software corrections have different actions. Class I Z-1520-2025 covers 85 Mobi pumps on Control-IQ+ software 7.9: faulty interpolation around a CGM data gap when the estimated glucose value exceeds 255 mg/dL can under- or over-deliver insulin, and the FDA-listed action says affected users should turn off Control-IQ+.² Shared Class II Z-0232-2026 covers Mobi 7.9.0.1 (and named t:slim X2 versions) paired with Dexcom G7: starting a new sensor session too soon can trigger an unexpected automatic correction bolus and hypoglycemia, so affected users must follow Tandem's sensor-pairing timing instructions until the correction is installed.³ Exact software and configuration determine which notice applies.

Which CGMs and algorithms it works with. The Mobi is a closed commercial AID system. It integrates in the US with Dexcom G6, standard G7, G7 15 Day, and Abbott's FreeStyle Libre 3 Plus, and runs Tandem's Control-IQ+ algorithm, which reads CGM values, predicts glucose 30 minutes ahead, and automatically adjusts insulin every five minutes.^1012413 It has no official DIY/open-source looping support. The underlying Control-IQ algorithm was tested in the pivotal NEJM randomized trial (Brown et al., raising time-in-range from 61% to 71%),¹⁴ and real-world Control-IQ+ data show ~71% median time in range across 40,000+ users.¹⁵

Phone bolusing. The Mobi is fully controllable from a compatible iOS or Android smartphone — you can bolus for meals and adjust settings directly from the app.¹⁰⁹⁸ An on-pump quick-bolus button also lets you deliver a bolus in programmable increments without your phone as a backup.⁹

Pregnancy indication. On 27 April 2026 the FDA cleared Control-IQ+ on both Mobi and t:slim X2 for pregnancy complicated by type 1 diabetes; Tandem announced the corresponding European CE-mark expansion on 5 June 2026.⁶⁷ The randomized CIRCUIT evidence behind that label tested Control-IQ on t:slim X2 hardware, so it supports the shared algorithm and pregnancy indication rather than a Mobi-specific hardware trial.

Access and cost. The Mobi is established in the United States for people aged 2 and older.¹⁰ Tandem reported on 6 August 2026 that an international commercial rollout had begun during Q2, though its filing did not identify the first countries or support a claim of blanket availability across Europe, Canada or Australia.⁴ In the US it is distributed through durable-medical-equipment and pharmacy channels depending on payer coverage.

What's coming. Tandem is developing a tubeless version of the Mobi: the same pump body would slide into an adhesive patch (via a side-clip design) using a new 7-day SteadiSet infusion set, making it a first-of-its-kind hybrid that can be worn either tubed or tubeless.¹⁶ The company confirmed that it submitted the 510(k) in Q2 2026.⁴ Submission is not FDA clearance, so today Mobi remains a tubed pump and no launch date is assured.