# TDF Calculator vs ESTRO 2026

The clearest difference is review sentiment: TDF Calculator at 67% against ESTRO 2026's 0%. TDF Calculator also leads on iOS requirement (8.0 vs 15.5). ESTRO 2026's advantage is update cadence (weekly vs every 3 weeks). On price, ads, in-app purchases and monetization model there is nothing between them.

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

TDF Calculator ships an update every 3 weeks, ESTRO 2026 weekly. The most recent releases landed on September 25, 2026 and October 20, 2026 respectively.

## The numbers

| Metric | TDF Calculator | ESTRO 2026 |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/tdf-calculator/id900087159/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | **66.7% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Weekly** |
| Monetization | Free | Free |
| Size | 14 MB | 100 MB |
| Requires iOS | **8.0** | 15.5 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 17+ |
| Developer | [Hiroyuki KATOH](https://appshunter.io/developer/898546586) | [CYIM](https://appshunter.io/developer/394180060) |

## What reviewers say

### TDF Calculator

[App page](https://appshunter.io/ios/app/tdf-calculator/id900087159)

This app simplifies the calculation of normal tissue tolerance dose in radiotherapy using the TDF factor. It offers an easy-to-use interface for radiation oncology professionals to quickly obtain results and understand the impact of fractionation on different tissues.

**Highlights:** Calculates TDF factors for normal tissue tolerance dose, Supports two TDF factor versions (1973 and 1986), Calculates TDF factors for three different conditions simultaneously, Automatically sums TDF factors, Calculates related total or fraction dose, Organizable with URL scheme

**Features:** macOS Compatibility

**In-app purchases:** none


### ESTRO 2026

[App page](https://appshunter.io/ios/app/estro-2026/id1614477899)

Access the full program, engage during sessions, and view posters for a leading radiation oncology congress. This app facilitates learning, collaboration, and connection within the medical community.

**Highlights:** Access congress program, Interact during sessions, Watch session replays, View posters, Connect with community

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is TDF Calculator free?

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

### Is ESTRO 2026 free?

ESTRO 2026 is free to download, with no in-app purchases.

### Do TDF Calculator or ESTRO 2026 have ads?

Neither TDF Calculator nor ESTRO 2026 shows ads.

### Which is updated more often, TDF Calculator or ESTRO 2026?

TDF Calculator ships an update every 3 weeks, and ESTRO 2026 weekly. Most recently, TDF Calculator was updated on September 25, 2026 and ESTRO 2026 on October 20, 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.*