Tandem Mobi (Control-IQ+)

The Tandem Mobi is described by the company as the world's smallest durable automated insulin delivery (AID) system — a miniature tubed pump less than half the size of Tandem's t:slim X2, small enough to fit in a coin pocket.¹⁰ It holds 200 units of insulin, recharges wirelessly by inductive charging, and is rated water-resistant (IP28, tested at 8 feet for 2 hours).³ It is fully controllable from a compatible smartphone app — there is no pump screen — though an on-pump button lets you bolus or disconnect without your phone.³

Components. Mobi is one corner of a three-part system: the pump, a Dexcom CGM (it integrates in the US with Dexcom G6, standard 10-day G7 and, since Q2 2026, G7 15 Day), and the Control-IQ+ algorithm.³⁴ Control-IQ+ reads CGM values, predicts glucose 30 minutes ahead, and adjusts insulin every 5 minutes, adding automatic correction boluses (AutoBolus) to head off highs.³

Evidence — read this carefully. Mobi is new hardware, but it runs the same algorithm as the t:slim X2, so its trial evidence is inherited rather than Mobi-specific. In the pivotal 6-month DCLP3 randomized trial of that algorithm, time in range (70-180 mg/dL) rose from 61% to 71% (a +11 percentage-point gain vs a sensor-augmented pump), time below 70 mg/dL fell by 0.88 points, and HbA1c dropped 0.33 points — with the system in closed-loop mode ~90% of the time.¹¹ A real-world analysis of 9,451 users found time in range climbing to ~74% and time below range steady near 1%, matching or beating the trial.¹² In children, one-year real-world use lifted TIR from 51.6% to 64.4% and cut HbA1c from 7.8% to 7.1%.¹³ In 2025 the algorithm was also validated in type 2 diabetes: a 319-person NEJM randomized trial showed TIR rising from 48% to 64% and an adjusted HbA1c reduction of 0.6 points over 13 weeks.¹⁴

Automation level. This is a hybrid closed loop, not fully closed. You still count carbs and announce meals; the algorithm handles the background and issues auto-corrections, but it cannot yet absorb a surprise meal on its own.¹¹ A manual Exercise Activity raises the glucose target during activity, and a Sleep Activity tightens overnight control — both switched on by the user, not detected automatically.³

Ages and indications. Mobi is FDA-cleared for people aged 2 and older.³ The underlying Control-IQ+ algorithm is cleared for type 1 diabetes and, since February 2025, for adults with type 2 diabetes who use insulin.¹⁵

Pregnancy. On 27 April 2026 the FDA cleared Control-IQ+ on both Mobi and t:slim X2 for pregnancy complicated by type 1 diabetes, and Tandem announced a corresponding European CE-mark expansion on 5 June.⁸⁹ The CIRCUIT randomized trial used t:slim X2 hardware, so the evidence is for the shared algorithm and pregnancy indication rather than a Mobi-specific hardware trial.

Open FDA corrections. Three current records have different scopes and actions. Class I Z-0427-2026 covers 17,745 pumps on versions 7.6.0.1, 7.6.0.3 or 7.7.0.1: a false Malfunction 12 can stop insulin; version 7.9.0.2 or later fixes that defect specifically.⁵ Class I Z-1520-2025 covers 85 pumps on Control-IQ+ 7.9 whose CGM-gap interpolation can under- or over-deliver; the FDA-listed action says affected users should turn Control-IQ+ off.⁶ Class II Z-0232-2026 covers Mobi 7.9.0.1 and named t:slim X2 versions paired with Dexcom G7, where sensor-session timing can trigger an unexpected autobolus; users must follow Tandem's timing instructions until corrected.⁷ These are corrections, not a withdrawal of every Mobi, and the exact software/configuration determines which action applies.

Access. The US remains Mobi's established market, distributed through pharmacy and durable-medical-equipment channels. Tandem reported on 6 August 2026 that international commercial rollout had begun during Q2, but the filing did not name the first countries or quantify availability.⁴ That supports a real rollout, not blanket availability across the UK, EU, Canada and Australia.

What's coming. Mobi launched controlled only by iPhone, but in November 2025 the FDA cleared an Android version of the app, and Tandem made it available on March 4, 2026 for Google Pixel 6-10 and Samsung Galaxy S21-S25 phones — removing the iPhone-only barrier.¹⁶ Because Mobi receives wireless over-the-air software updates,¹⁰ future algorithm improvements toward fuller meal automation can reach the same hardware without a new pump. Tandem also submitted a 510(k) for a tubeless Mobi wearing option in Q2 2026; that is an application under review, not a clearance or launch.⁴