片手で打てる便利な電卓 - 履歴・日付・メモ・カーソル移動

A must-have app for the era of large-screen smartphones. This free, highly functional, and easy-to-use calculator is designed for one-handed operation.

"Today's smartphones are so big, my fingers can't reach the edge buttons..." "I made a mistake at the end of a long calculation and had to start over..." "I forgot to write down the numbers I just calculated..."

This calculator was developed to relieve the stress of everyday calculations. It's packed with features you won't find in standard calculator apps, including one-handed mode, cursor movement, calculation history, memo function, date calculations, and consumption tax settings.

It's useful in a variety of situations, including business, office work, household accounting, splitting bills, studying, and DIY dimension calculations.

━━━━━━━━━━━━━━━━━━━━━ 🌟 Reasons to choose this "convenient one-handed calculator" ━━━━━━━━━━━━━━━━━━━━━

✅ 1. Your fingers can reach it! Comfortable One-Handed Mode
Even with increasingly larger smartphone screens, you can comfortably operate the calculator with just one thumb.

Left/Right Alignment Support: You can align the keypad to the right or left side of the screen. It's fully compatible with both right- and left-handed users.

Utilize Free Space: The space opposite the keypad can be used to store calculation history and control buttons. Use the screen efficiently.

Size Adjustment: Calculate in the most comfortable position for your hand. You can input data smoothly even while holding onto a strap on a crowded train or carrying luggage.

✅ 2. Cursor Control: No need to worry about making mistakes
Move freely through formulas, just like in a PC text editor.

Arrow Key Movement: Use the ← and → buttons to move the cursor and correct any mistakes.

Mid-Text Insertion/Deletion: Add numbers to formulas or delete single characters with backspace.

Easy All-Erasing: Press and hold backspace to clear all entries at once.

Parentheses: Easily add parentheses later, even for calculations with precedence, such as (100 + 200) × 3, using the cursor.

✅ 3. History & Memo Function: Serves as a Memory
Don't worry if you forget the result after tapping on the calculator.

Auto-save: Up to 50 calculation results and formulas are automatically saved in the history. They will not be deleted even if you close the app.

Note Input: Enter titles and notes for each history entry. By writing things like "Food Expenses," "Company A Estimate," or "November Spectroscopic Utility Expenses," you can easily see what values ​​they represent when you review them later.

Favorites: Lock important calculation results you don't want to lose (add them to favorites) with a single tap.

Reuse: Tap a history formula to recalculate, or insert just the result into the current formula.

Clipboard: Easily copy results and paste them into LINE, email, Excel, and more.

✅ 4. Practical Calculation Functions to Speed ​​Up Office Work
Dedicated modes are included for calculations frequently used in work and daily life.

📅 Date Calculator (Period/Day Calculations) No need to count down the days while looking at a calendar.

Day Calculation: Instantly calculate questions like, "What date is it x days from today?" or "How many days until the project deadline?"

Date Calculation: Easily calculate questions like, "How many days are there between January 1, 2025 and March 31, 2025?"

Time Calculation: In addition to days, it also supports time calculations like, "What time is it x hours from now?" or "What time is x minutes ago?"

💰 Consumption Tax and Discount Calculation: Powerfully supports tax calculations, essential for shopping and accounting.

One-Tap Tax/Tax Included/Excluded: Simply enter the amount and press a button to switch between tax-inclusive and tax-exclusive prices.

Tax Rate Settings: Freely set your preferred tax rate, including 10%, 8% (reduced tax rate), and even accommodate future tax rate changes and overseas tax rates.

Tax Display: Instantly see how much the tax is included.

Compatible with Standard Mode: The standard calculator screen features "Tax Included" and "Tax Excluded" buttons, eliminating the need to switch modes.

✅ 5. Customize the Look and Sound: Because it's a tool you use every day, we've focused on creating a design you'll love.

Color Themes: Choose from four themes, including the energetic "Retro Orange," the intellectual "Ocean Blue," and the calming "Grayscale."

Dark Mode: Match your smartphone's system settings or customize your own dark mode. Work at night without straining your eyes.

Sound Settings: Turn the electronic click sound (clicking sound) on or off when you press a key.

Haptics (Vibration): The device features a vibration function that sends a thumping sound to your fingertips the instant you press a button. You'll get a tactile feedback to let you know whether your input was successful, reducing typos.

━━━━━━━━━━━━━━━━━━━━━ 📚 Useful in the following situations ━━━━━━━━━━━━━━━━━━━━━━━

While shopping at the supermarket: Calculate the total while holding the basket in one hand. Prevent overspending.

When splitting bills: Divide the total by the number of people, then note "¥X per person" and save the history. Convenient for sharing later.

Creating estimates for work: The visible formula makes calculations easy to check, and you can calculate consumption tax without making mistakes.

Planning a trip: Manage your schedule, such as the number of days left until departure and the number of days you'll be staying.

DIY and sewing: Use parentheses and correction functions to easily perform calculations like "Divide 150cm of fabric into thirds and add 2cm to the seam allowance."

━━━━━━━━━━━━━━━━━━━━━ ⚙️ Main Specifications and Features ━━━━━━━━━━━━━━━━━━━━━

[Basic Calculations]

Arithmetic operations (addition, subtraction, multiplication, division)

Calculations using parentheses

Percentage calculations (%)

Backspace (delete one character / hold to delete all)

Cursor movement (← / →)

Edit formulas mid-calculation

[Display & Layout]

One-handed mode (switch between right-justified and left-justified)

Always display formulas (allows you to check your input)

Commas display between thousands

Supports calculations with 10 or more digits

[History & Memory]

Automatically save calculation history (up to 50 entries)

Add text notes to history

Favorites (protection feature)

Delete history individually / delete all

Load formulas from history / Call Results

Copy Calculation Results to Clipboard

[Special Calculations]

Date Calculation (X Days Later, X Days Ago, Difference in Days)

Time Calculation (X Hours Later, X Minutes Later)

Consumption Tax Calculation (Customizable Tax Rate, Tax Included)

[Customization]

Selectable Theme Colors (4 Colors)

Light Mode / Dark Mode

Tap Sound (ON/OFF)

Vibration (ON/OFF)

━━━━━━━━━━━━━━━━━━━━━━ 📩 Support & Other ━━━━━━━━━━━━━━━━━━━━━━

This app is developed in Japan. If you have any questions about how to use the app, have any feature requests, or would like to report any bugs, please feel free to contact us via the in-app settings screen or by email at the address listed below. We value your reviews and feedback and will continue to update the app with the aim of making it the best calculator app available.

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