ZoneClock vs TriTab Calc

ZoneClock helps you instantly convert time across time zones with a clean, minimalistic UI. Simply enter a time in one location, choose another city, and see the exact local time immediately. Designed for travel, remote teams, and anyone working across time zones, with full offline support.

A three-tab calculator that lets you keep multiple calculations going at the same time. The A, B, and C tabs each work as an independent calculator. Switch between them without losing your current expression or result. Use A for the pre-tax price, B for the tax-inclusive total, and C for the discounted price—all without writing down intermediate numbers or clearing your work. One purchase unlocks everything. No ads, no in-app purchases, no subscriptions. ■ Running Total as You Type The answer so far appears in small text below your expression, so you can check a running total before you press "=". ■ Three Independent Calculators Switch between A, B, and C with one tap. Each tab keeps its own expression and result, so you can work on three calculations in parallel. ■ Compare All Three See the total of all three tabs and the difference between the highest and lowest at a glance. ■ Tax In and Out Add tax with one tap, or work back from a tax-inclusive price to the pre-tax amount. Set any tax rate in Settings. ■ Split the Bill Enter a total and the number of people to get the amount per person, with optional rounding up. ■ History, Copy and Undo Each tab keeps its own history. Tap an entry to copy its result. Tap the display to copy or paste, touch and hold to clear. Undo and redo are supported. ■ Essential Calculator Functions Basic arithmetic plus square root (√), square (x²), percentages (%), sign change (±), parentheses, and a 00 key. ■ Easy on the Eyes Choose from four themes—Pastel, High contrast, Dark, and Night—and turn on Large text when you need it. ■ Four Languages English, Japanese, Simplified Chinese, and Traditional Chinese. The app follows your device language automatically. ■ Perfect For • Checking estimates and invoices • Comparing pre-tax, tax-inclusive, and discounted prices • Calculating sales tax and shopping discounts • Splitting bills and calculating per-person costs • Comparing unit prices • Adding up inventory and quantities ■ Privacy Your calculation history and settings are stored only on your device. No account is needed, and the app does not collect personal information or send your data to external servers.