# SMS Alert vs IR Heat Map

The clearest difference is rating: SMS Alert at 5.0 against IR Heat Map's 3.0. SMS Alert also leads on iOS requirement (9.0 vs 13.0). IR Heat Map's advantage is update cadence (every 5 weeks vs every 14 months). On price, review sentiment, ratings volume and ads there is nothing between them.

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

SMS Alert holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 1 and 2 respectively. Written reviews split almost evenly too, at 0% and 0% positive.

SMS Alert ships an update every 14 months, IR Heat Map every 5 weeks. The most recent releases landed on October 22, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | SMS Alert | IR Heat Map |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/sms-alert/id1100172188/reviews)** | [3.0 (2 ratings)](https://appshunter.io/ios/app/ir-heat-map/id6740187644/reviews) |
| Number of ratings | 1 | **2** |
| Positive reviews | 0.0% of reviews | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 14 months | **Every 5 weeks** |
| Monetization | Free | Free |
| Size | 7 MB | 72 MB |
| Requires iOS | **9.0** | 13.0 |
| Devices | iPhone, iPod | iPhone, iPod |
| Age rating | 4+ | 17+ |
| Developer | [朝山 马](https://appshunter.io/developer/596304901) | [永强 陈](https://appshunter.io/developer/1771010405) |

## What reviewers say

### SMS Alert

[App page](https://appshunter.io/ios/app/sms-alert/id1100172188)

This app monitors temperature, humidity, analog signals, and power status for various devices. It sends alerts via SMS and phone calls when predefined limits are reached. Users can also query device status via text and schedule periodic reports.

**Highlights:** Temperature and humidity monitoring, Analog signal monitoring (4-20mA, 0-5V), Power monitoring (single/three-phase), SMS and phone call alerts, Remote status query via text, Scheduled status reporting, Modbus RTU/TCP cloud platform support

**Features:** macOS Compatibility

**In-app purchases:** none


### IR Heat Map

[App page](https://appshunter.io/ios/app/ir-heat-map/id6740187644)

This thermal imager app integrates temperature measurement and imaging, offering a wide range from -20 to 550℃. It supports wireless screen projection and real-time analysis for various applications like HVAC, electrical maintenance, and equipment inspection.

**Highlights:** Temperature measurement (-20 to 550℃), Infrared thermal imaging, Wireless screen projection, Real-time analysis, Ease of use, Image observation via APP

**In-app purchases:** none


## Frequently asked questions

### Is SMS Alert free?

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

### Is IR Heat Map free?

IR Heat Map is free to download, with no in-app purchases.

### Which has better reviews, SMS Alert or IR Heat Map?

SMS Alert is rated higher. SMS Alert averages 5.0 out of 5 from 1 ratings, while IR Heat Map averages 3.0 from 2 ratings.

### Do SMS Alert or IR Heat Map have ads?

Neither SMS Alert nor IR Heat Map shows ads.

### Which is updated more often, SMS Alert or IR Heat Map?

SMS Alert ships an update every 14 months, and IR Heat Map every 5 weeks. Most recently, SMS Alert was updated on October 22, 2026 and IR Heat Map on October 30, 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.*