About this app
Derrick is the rotation calendar built for oilfield hands — and it actually keeps your hitch straight. Pick your rotation once (14/14, 14/7, 7/7, 21/21, 28/28, or a custom on/off), set the day your hitch starts, and Derrick paints your ON and OFF days correctly — for years. No drift. No "off by a day." No blank calendar when the new year rolls over. That sounds basic. It's the thing every other oilfield calendar gets wrong. NEW — Crew Pass. Send your rotation to your crew or your spouse as a code and a QR. They scan or paste it and import your whole schedule in one tap — no re-typing dates, no getting a day wrong. Free, offline, no account. FREE • Big, glanceable countdown — HOME IN __ DAYS / BACK IN __ DAYS • Today at a glance — "On hitch · Day 9 of 14" • Full month calendar with your ON/OFF days in color — scroll years ahead or back • Agenda of your upcoming hitches and time off, with exact dates • Crew Pass — share your rotation as a code/QR; your crew imports it in one tap • Home Screen & Lock Screen widgets • Crew-change reminders the evening before • Day & night shifts • 100% offline. No account, no sign-up, nothing leaves your phone. DERRICK PRO — one-time unlock (no subscription) • Whole year on one page — export a clean, printable PDF (one year per page, not 12 separate months) • Plan your life around your hitch — add birthdays, weddings, hunting season, the kids' games, and see instantly whether you'll be home or working • Track your money — pay, per-diem, days worked & overtime, in your currency (USD, CAD, GBP, AUD, NOK, EUR & more) Buy Pro once and keep it. No subscriptions. No ads. No data collection. Crew change shouldn't be this hard to track. Now it isn't.
Latest release
What’s New
What's new in 1.3 • My Crew keeps your rotation and adds one spouse or crewmate from their Crew Pass — no more replacing your own schedule. • See both schedules together and the next day you're both home, all offline. • Free, private, and fully offline — no account or subscription.
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 23, 2026 · 1:23 PM Free
Screenshots
