Conversion Calculator vs Happened
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Conversion Calculator
Easily convert between metric and imperial units for weight, length, temperature, area, and time. This app offers precise, fast results with a clean interface, working offline for daily, travel, school, or work needs.
- Metric and imperial unit conversion
- Weight, length, temperature, area, time
- Offline functionality
- Precise and fast results
- Clean and minimal interface
- Over 100 measurement types
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Convert cooking measurements, kg to lbs, feet to meters, Celsius to Fahrenheit and psi to bar in a tap. Conversion Calculator is a fast, clean unit converter for the kitchen, travel, the gym, school and work. COOKING & KITCHEN • Cups, tablespoons, teaspoons, fluid ounces, pints, quarts and gallons • US and imperial (UK) cups, pints and gallons kept separate, so recipes come out right • Grams, ounces and pounds for baking WEIGHT & BODY • kg to lbs, stones, ounces, grams and milligrams LENGTH, AREA & LAND • Feet, inches, meters, cm, miles, km, yards and nautical miles • Square feet, square meters, acres and hectares TEMPERATURE, SPEED & MORE • Celsius, Fahrenheit and Kelvin • km/h, mph, knots and m/s • Energy: calories, kcal, joules and kWh • Data: bytes, KB, MB, GB and TB • Time: seconds to hours PRESSURE, FUEL, POWER & MORE • Pressure: psi, bar, kPa, atm, mmHg and inHg • Fuel economy: mpg (US and UK), L/100 km and km/L • Power: horsepower (hp), kW and watts • Torque: N·m, lbf·ft and kgf·m • Force: newtons, lbf and kgf • Angle: degrees, radians and gradians MADE FOR EVERYDAY USE • 15 categories and 120+ units, metric and imperial • Swap units in one tap and copy the result • Reorder categories so the ones you use are on top, or hide the rest with Pro • Choose how many decimals to show • Apple Watch app for conversions on your wrist • Works offline Converting is free. Pro is an optional one-time purchase.
Happened
Easily log life events with customizable tags and analyze them using various metrics. Track symptoms, hobbies, or any personal occurrence with a simple tap and visualize your data over time. The app prioritizes your privacy, storing data locally or in your iCloud.
- One-tap event logging
- Four tag types: Valueless, Quantified, Balance, Binary
- Timeline divided into five parts of the day
- Drag and drop tag management
- 10 types of visual metrics
- Customizable time ranges for analytics
- CloudKit data storage for privacy
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This app was made for personal use, but it turned out too good to hide from the App Store. Log events happening in your life with one simple tap. Whether it’s symptoms, birdwatching, superstitions, you name it. Collect data and analyze it with metrics. Taxonomy The app supports four types of tags: - Valueless: Just to log events that happened. - Quantified: Each event has a numeric value. Users can also add a measurement unit. - Balance: Events have a visual gauge in the range of –1 to 1. Suitable for cases such as “better or worse than the baseline”. - Binary: Events have a true or false value, representing the outcome of an event. Timeline To speed up the creation and management of events, the day is divided into five parts. Tapping on a tag creates an event in the current part of today. Drag & drop tags to add events to any part of any day. Management Tags are categorized into groups, each with its own color. Add, edit and move your tags without losing associated events. Analytics The app offers 10 types of metrics to visually represent data, including counters, min/avg/max calculators, pie charts, linear graphs, and more. Each tag type has a specific set of metrics. Each metric can be limited by a time range: last week or the last one, three, six, or twelve months. Convenience - Gestures: swipe left and right on the timeline to navigate between days. Double-tap on the timeline returns to today’s view. - Swiping right on the Tag Groups stripe reveals a sandwich glyph (three horizontal lines). Dragging it vertically changes the height of the area with tags. - Change the order of Tag Groups and Metrics by holding and dragging them in the corresponding sections. - The plus glyph in the tag area on the home screen allows you to quickly add a new tag to the selected group. Privacy All your data is stored using the CloudKit framework provided by Apple. This means it’s either stored locally on the device or in your iCloud account. For encryption, opt into Advanced Data Protection in your iCloud settings (availability may vary by region). In any case, the developer DOES NOT have access to user data. The app DOES NOT use any analytics tools, so feel free to log your sensitive data. It stays only with you and no one else.
Screenshots
Verdict
The clearest difference is review sentiment: Conversion Calculator at 100% against Happened's 0%. Conversion Calculator also leads on rating (4.8 vs 3.7) and ratings volume (165 vs 3). Happened's advantage is in-app purchases (none vs 1). On price, update cadence, ads and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Conversion Calculator sells 1 one-off in-app purchase. Happened asks for nothing beyond the download.
Conversion Calculator holds the better App Store score, 4.8 against 3.7. That said, the two scores are not equally well evidenced: Conversion Calculator has 165 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 100% of Conversion Calculator's written reviews are positive against 0% of Happened's.
Conversion Calculator ships an update every 5 weeks, Happened monthly. The most recent releases landed on October 30, 2026 and October 22, 2026 respectively.
| Parameter | Conversion Calculator | Happened |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (165 ratings) — better | 3.7 (3 ratings) |
| Positive reviews | 100.0% of reviews — better | 0.0% of reviews |
| Number of ratings | 165 — better | 3 |
| Update frequency | Every 5 weeks | Monthly — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad, Apple Watch — better | iPhone |
| Requires iOS | 17.0 — better | 17.6 |
| Further details — not scored | ||
| Size | 10 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | Collins Cheruiyot | Pavel Shlyapnikov |
Customer experience
Conversion Calculator
Happened
In-app purchases
Conversion Calculator
- Unlimited access forever$8.99
Happened
No in-app purchases
Questions
Is Conversion Calculator free?
Is Happened free?
Which has better reviews, Conversion Calculator or Happened?
Do Conversion Calculator or Happened have ads?
Which is updated more often, Conversion Calculator or Happened?
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