# back2book vs Water Flash

The clearest difference is ads: back2book at none against Water Flash's shown. back2book also leads on device support (3 vs 1) and iOS requirement (14.0 vs 16.6). Water Flash's advantage is update cadence (every 3 weeks vs every 8 months). On price and in-app purchases there is nothing between them.

Both are free to download. back2book sells 1 one-off in-app purchase and Water Flash sells 2 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

back2book ships an update every 8 months, Water Flash every 3 weeks. The most recent releases landed on October 7, 2026 and October 1, 2026 respectively.

## The numbers

| Metric | back2book | Water Flash |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 57.1% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 8 months | **Every 3 weeks** |
| Monetization | Free with in-app purchases | — |
| Size | 3 MB | 12 MB |
| Requires iOS | **14.0** | 16.6 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [TinkaTinka](https://appshunter.io/developer/505803809) | [Elena Anghel](https://appshunter.io/developer/1780729890) |

## What reviewers say

### back2book

[App page](https://appshunter.io/ios/app/back2book/id714095374)

Create a printable backup of your iPhone contacts. Easily generate a wallet-sized paper phone book from your stored numbers. Perfect for ensuring you always have important contacts accessible, even without your device.

**Highlights:** Paper backup of phone numbers, Create wallet-sized phone book, Simple and fast process, Uses normal printer, Backup all stored contacts

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Full Version | $0.99 | one-time |


### Water Flash

[App page](https://appshunter.io/ios/app/water-flashwaveflush/id6751397090)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Subscription | $4.99 | per 7 days |
| Yearly Subscription | $24.99 | per year |


## Frequently asked questions

### Is back2book free?

back2book is free to download, with in-app purchases available.

### Is Water Flash free?

Water Flash is free to download, with in-app purchases available.

### Do back2book or Water Flash have ads?

Water Flash shows ads; back2book does not.

### Which is updated more often, back2book or Water Flash?

back2book ships an update every 8 months, and Water Flash every 3 weeks. Most recently, back2book was updated on October 7, 2026 and Water Flash on October 1, 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.*