# PrefixPlus vs CarKeeper

The clearest difference is review sentiment: PrefixPlus at 72% against CarKeeper's 13%. PrefixPlus also leads on rating (4.7 vs 2.9) and ratings volume (1.1K vs 11). CarKeeper's advantage is ads (none vs shown) and monetization model (free vs ad-supported). On price, update cadence, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

PrefixPlus holds the better App Store score, 4.7 against 2.9. That said, the two scores are not equally well evidenced: PrefixPlus has 1.1K ratings behind it against 11, so its average is the more settled of the two. Written reviews point the same way: 72% of PrefixPlus's written reviews are positive against 13% of CarKeeper's.

Both ship on a similar rhythm, roughly every 2 months. Both last shipped on October 24, 2026.

## The numbers

| Metric | PrefixPlus | CarKeeper |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (1.1K ratings)](https://appshunter.io/ios/app/prefixplus-add-the-prefix/id1142430837/reviews)** | [2.9 (11 ratings)](https://appshunter.io/ios/app/carkeeper/id1444288968/reviews) |
| Number of ratings | **1.1K** | 11 |
| Positive reviews | **71.8% of reviews** | 12.7% of reviews |
| In-app purchases | No | No |
| Ads | Yes | **No** |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | Ad-supported | **Free** |
| Size | 8 MB | 54 MB |
| Requires iOS | 15.6 | **9.0** |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [yasuhiko nagahara](https://appshunter.io/developer/1142430836) | [清贤 高](https://appshunter.io/developer/1192185896) |

## What reviewers say

### PrefixPlus

[App page](https://appshunter.io/ios/app/prefixplus-add-the-prefix/id1142430837)

Easily add international or custom prefixes to all your phone numbers in contacts simultaneously. This utility helps manage multiple contact entries for different calling regions without overwriting existing numbers. Ensure you back up your contacts before use.

**Highlights:** Add prefixes to multiple contacts at once, Does not overwrite existing numbers, Customizable prefix numbers, Customizable label for new entries, Supports iCloud and Gmail synchronized contacts

**Features:** macOS Compatibility

**In-app purchases:** none

**What reviewers like**

- 💡 Allows adding prefix numbers to contacts
- 🚀 Efficient batch update of contacts
- 👍 Convenient for users of MVNO services
- 👍 Integrates well with default phone app

**What reviewers complain about**

- 🐛 Crashes or freezes when updating contacts
- 🐛 Inconsistent or incomplete contact updates
- 🔋 Potential for increased data usage or charges

**Reported bugs**

- Crashes on iOS 13.3
- Duplicate contact entries created
- Prefix not applied to all contacts

**Requested features**

- Option to add space between prefix and number
- Support for local/offline contacts
- Ability to selectively update contacts


### CarKeeper

[App page](https://appshunter.io/ios/app/carkeeper/id1444288968)

Manage your vehicle's maintenance and expenses with this smart car housekeeper. Track service history, fuel consumption, and important dates. Keep your car running smoothly and efficiently.

**Highlights:** Vehicle maintenance tracking, Expense logging, Service history, Fuel consumption monitoring, Important date reminders

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is PrefixPlus free?

PrefixPlus is free to download, with no in-app purchases.

### Is CarKeeper free?

CarKeeper is free to download, with no in-app purchases.

### Which has better reviews, PrefixPlus or CarKeeper?

PrefixPlus is rated higher. PrefixPlus averages 4.7 out of 5 from 1.1K ratings, while CarKeeper averages 2.9 from 11 ratings.

### Do PrefixPlus or CarKeeper have ads?

PrefixPlus shows ads; CarKeeper does not.

### Which is updated more often, PrefixPlus or CarKeeper?

PrefixPlus ships an update every 2 months, and CarKeeper every 2 months. Most recently, PrefixPlus was updated on October 24, 2026 and CarKeeper on October 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*