Apptopia's mobile app data shows the Amazon backed robotaxi grew from 15% to 25% of US robotaxi monthly active users between January and June 2026, while Waymo slipped from 79% to 69%.
Zoox's share of US robotaxi app users doubled to 25% between January and June 2026, according to Apptopia data first reported by Business Insider. Waymo's share fell from 79% to 69% over the same six months. It is the first sustained share erosion Waymo has posted since it scaled, and the operator behind it is running a very different playbook.
Apptopia measures installs and app opens, not rides, fares, or unique riders across all booking channels. So its share figure tracks which robotaxi app is winning new user attention, not which operator is collecting the most fares. The direction of travel is hard to miss: Zoox's monthly active user growth has run at double-digit monthly rates through the first half, while Waymo's year-over-year MAU growth dropped from 79% in early 2025 to about 15% by mid-2026, per the same Apptopia dataset.
Zoox is winning on distribution, not just on geography. It runs a retrofitted Toyota Highlander fleet in Atlanta, Austin, Los Angeles, Miami, Seattle, and Washington, and has been gradually expanding its San Francisco service area. The growth lever for the back half of 2026 is a planned launch on the Uber app in Las Vegas this summer, per CNBC's December 2025 expansion roadmap, which would let riders book a Zoox without installing its own app. The company is also scaling production at its Hayward, California factory toward roughly 100 vehicles a week and unveiled a purpose-built production robotaxi on June 24–25, 2026.
Outside China, Waymo remains the only operator running a direct-bookable, fare-charging, fully driverless service in multiple cities at the same time, per The Driverless Digest's industry overview. Tesla's commercial driverless footprint is narrower: its Robotaxi app does not yet match the booking depth of Waymo One or Zoox, and a meaningful slice of any Tesla robotaxi MAU figure still reflects waitlists and supervised rides rather than fare-paying driverless service. The 10-point swing in Apptopia's data is therefore a story about where new app curiosity is landing, not about Tesla losing riders it had.
Waymo's vertical integration buys operational control and a direct line to riders, with one app and one brand. Zoox's platform-partnership model buys app reach without owning the customer relationship: a Las Vegas rider who searches Uber for a robotaxi gets a Zoox without ever downloading it. The economics work differently too. A partnership-driven MAU curve is bounded by Uber's user base and willingness to surface robotaxi inventory, while a vertically integrated curve is bounded by Waymo's own fleet production and city rollouts. Zoox's 10-point share gain in six months suggests the partnership curve is currently the steeper one, and that is the line the Hayward factory has to feed if the model is to scale beyond a handful of cities.
Zoox's near-term watch item is the Las Vegas launch window, which The Charge Port's Robotaxi Tracker pegs for summer 2026. The launch will be the first time Zoox books a meaningful share of its rides through an outside app rather than its own, and the first test of whether the Uber partnership scales the same way the multi-city Highlander rollout did in the first half. Apptopia's July print, due in early August, will be the cleanest read on which side of the 25% line the data lands.