A small iOS development studio

We build software that
respects the data you put into it.

TwistedData Studios is a tiny, opinionated studio shipping native iPhone and iPad apps. Two are on the App Store, a third is in review, and a fourth is still on the bench. Each does its work on the device it runs on, without required accounts, without selling your data, and with every third-party SDK we depend on named openly in the privacy policy.

SolGlow
TripSnap
CalmTide
Dashboard Today 47 min sunlight 1240 IU vitamin D 207% of goal Last 7 days Deficiency Risk LOW 18 / 100
Dashboard RECORDING 12.4 mi Recognized your car · Ford SYNC Started 8:14 AM · $8.99 so far UNCLAIMED $187.40 Oldest trip is 24 days old Tracking is healthy Always + Precise location · Motion · Bluetooth THIS MONTH 318 mi Business $230.55 Reimbursable
Today 72 HPA BALANCE Cortisol likely moderate today Today's recommendation Easy 30-min walk, then 5 minutes of slow breathing. Skip the hard session. HRV (SDNN) 58 ms ▲ trending up Deep sleep 1h 42m solid night
How we build

Three rules we don't break.

Every product we ship is held to the same three commitments. They shape what we can and can't build, and they're why our software feels different from what's around it.

On-device by default

What you enter and what we calculate stays on your phone wherever it can. Servers are an absolute last resort, and we tell you when one is touched.

No required accounts

Our apps work without you signing up for anything. Where we offer Sign in with Apple, it's optional and used only for a single, named feature — never as a gate.

Honest UI

Estimates are clearly labeled as estimates. Simulations are clearly labeled as simulations. We'd rather say "we're not sure" than fake precision.

Apps

What we ship.

Two live on the App Store and one in review. SolGlow and CalmTide are companions — connect both and they share data on-device to get smarter. A fourth app, Hedge Fund CEO, is still in development — it's on the roadmap below.

Live · Free · Pro from $9.99
SolGlow
Health & Fitness · iPhone + Apple Watch

A vitamin D companion for iPhone. Estimates the vitamin D you produced from sunlight today using your Apple Watch's Time in Daylight, your skin type, your location, and what you ate — all on the device.

  • Reads Apple Health Time in Daylight; writes vitamin D back as dietary samples.
  • Burn-risk warnings tuned to your Fitzpatrick skin type and the day's UV.
  • Weekly Sun Plan, Annual Plan, 60-day history with location-aware attribution.
  • New in 1.8: SolGlow Pro comes two ways — $9.99 a year or $19.99 once — with a redesigned icon and animated launch, atop v1.7 “The Real Number” (True-D ozone-corrected vitamin D, cited on screen, in German, Spanish & Japanese).
  • No account. No analytics. Just a single UV-forecast network call.
Download on theApp Store Product page
Live · Free · Pro from $4.99
CalmTide
Health & Fitness · iPhone + Apple Watch

A cortisol and HPA-axis tracker. Turns the HRV, sleep, and workout data your Apple Watch already collects into a weekly stress-balance score and an 8-week baseline-cortisol trend you can actually move.

  • Weekly HPA Balance Score from HRV, sleep, training load & breathwork.
  • Daily cortisol read with one smart, personalised recommendation.
  • 8-week baseline trend — the stress signal most apps never show.
  • New in 1.6: HRV measured while you actually sleep, sleep scored on regularity as well as hours, plus sleep continuity and social jetlag — atop 1.5's morning-after patterns and weekly “what moved your score” breakdown. 1.7 — no intensity credit for workouts without heart rate, training load as plain figures, an optional drink count — is in review.
  • Connects with SolGlow for morning-sun data. On-device, no account.
Download on theApp Store Product page
In review
TripSnap
Business · iPhone + iPad

An automatic mileage tracker that knows the difference between your car and a bus. It recognises the car you're sitting in, records the drive in the background, and builds the expense report that actually gets you reimbursed.

  • Starts because CarPlay or your saved car stereo connected — not because you moved.
  • Tracking Health card names the permission that broke, the day it breaks.
  • PDF expense report with the pay-period total on top, plus CSV, JSON and GeoJSON.
  • Two modes: employer reimbursement, or gig shifts with $/hour after fuel.
  • No account, no server, no employer dashboard — the log never leaves the phone.
In review for theApp Store Product page
4
apps built
0
data ever sold
100%
native SwiftUI
∅
required accounts
What's next

The road ahead.

A short, honest snapshot of what we're working on. We update this page when releases ship — not before.

Four apps, shipping one at a time.

We ship one focused release at a time — each when it's ready, not when a sprint board says it should. This list is kept current as builds ship and reviews clear.

  • Live · v1.8 SolGlow — vitamin D companion. Shipped Apr 2026, now on v1.8 “Choose how you pay” — Pro as a $9.99 yearly plan or a $19.99 one-time unlock, plus a new icon and animated launch, atop v1.7 “The Real Number.” See the update history →
  • Live · v1.6 CalmTide 1.6 — cortisol & HPA-axis tracker that connects with SolGlow. Now on v1.6 “What it actually measured”: HRV read from the night you actually slept, sleep scored on regularity as well as hours, plus sleep continuity and social jetlag. 1.7 is submitted for review. See the update history →
  • In review · Aug 2026 TripSnap 1.0 — automatic mileage tracker for people who get reimbursed for driving. Car-aware capture, a tracking-health monitor, pay-period expense reports, and a second mode for gig drivers. Read the product page →
  • Next SolGlow — a roomier iPad layout, plus localized App Store screenshots for the new German, Spanish, and Japanese listings.
  • Later CalmTide — multi-device iCloud sync (1.5 ships manual export & restore in the meantime) and deeper SolGlow ecosystem features.
  • In development Hedge Fund CEO 1.0 — stock-trading simulator. Still being built, and later than we first planned; we'd rather say so than keep quoting a date. Read what it does →
Press & resources

For writers and reviewers.

Short PDFs for each product with the headline numbers, the science (or the spec), and the privacy claims spelled out. Also where to point a link.

SolGlow marketing brochure

Five-page PDF — overview, features, the science, privacy. ↗

CalmTide marketing brochure

Overview, the HPA Balance Score, the science, and the privacy posture. ↗