# RD Smart Tax vs ERG4Thai

The clearest difference is update cadence: RD Smart Tax at every 4 weeks against ERG4Thai's every 3 months. On price, ads, 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.

RD Smart Tax ships an update every 4 weeks, ERG4Thai every 3 months. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | RD Smart Tax | ERG4Thai |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[2.5 (6 ratings)](https://appshunter.io/ios/app/rd-smart-tax/id616843710/reviews)** | — |
| Number of ratings | **6** | — |
| Positive reviews | 10.7% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 weeks** | Every 3 months |
| Monetization | Free | — |
| Size | 47 MB | 86 MB |
| Requires iOS | 13.0 | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | +17 |
| Developer | [Revenue Department (Thailand)](https://appshunter.io/developer/616843713) | [Pollution Control Department, Thailand](https://appshunter.io/developer/966167337) |

## What reviewers say

### RD Smart Tax

[App page](https://appshunter.io/ios/app/rd-smart-tax/id616843710)

This application simplifies filing personal income tax returns and accessing other electronic services from the Revenue Department. It offers a tax calendar, news alerts, tax calculation tools, and online submission for various tax forms. Users can also track tax refunds, find tax offices, and access educational resources.

**Highlights:** Tax calendar with deadlines, News and filing alerts, Tax calculation tool, Online tax form submission, Tax refund tracking, Revenue department office locator, Tax education resources

**In-app purchases:** none


### ERG4Thai

[App page](https://appshunter.io/ios/app/erg4thai/id1514892942)

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

**In-app purchases:** none


## Frequently asked questions

### Is RD Smart Tax free?

RD Smart Tax is free to download, with no in-app purchases.

### Is ERG4Thai free?

ERG4Thai is free to download, with no in-app purchases.

### Do RD Smart Tax or ERG4Thai have ads?

Neither RD Smart Tax nor ERG4Thai shows ads.

### Which is updated more often, RD Smart Tax or ERG4Thai?

RD Smart Tax ships an update every 4 weeks, and ERG4Thai every 3 months. Most recently, RD Smart Tax was updated on November 1, 2026 and ERG4Thai on November 3, 2026.

---

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