# ULTRAPEN™ PTBTx™ vs Solution Dilution Calculator

The clearest difference is review sentiment: ULTRAPEN™ PTBTx™ at 100% against Solution Dilution Calculator's 0%. ULTRAPEN™ PTBTx™ also leads on price (Free vs $2.99) and update cadence (every 5 months vs every 22 months). Solution Dilution Calculator's advantage is rating (5.0 vs 3.7) and iOS requirement (13 vs 15.0). On ads, in-app purchases and device support there is nothing between them.

ULTRAPEN™ PTBTx™ is free to download; Solution Dilution Calculator costs $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Solution Dilution Calculator holds the better App Store score, 5.0 against 3.7. Both are backed by a comparable volume of ratings — 3 and 1 respectively. Written reviews complicate that: 100% of ULTRAPEN™ PTBTx™'s written reviews are positive against 0% of Solution Dilution Calculator's, so the app with the better star average is not the one people write more warmly about.

ULTRAPEN™ PTBTx™ ships an update every 5 months, Solution Dilution Calculator every 22 months. The most recent releases landed on October 7, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | ULTRAPEN™ PTBTx™ | Solution Dilution Calculator |
| --- | --- | --- |
| Price | **Free** | $2.99 |
| Rating | [3.7 (3 ratings)](https://appshunter.io/ios/app/ultrapen-ptbtx/id885545007/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/solution-dilution-calculator/id1353265965/reviews)** |
| Number of ratings | **3** | 1 |
| Positive reviews | **100.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 5 months** | Every 22 months |
| Monetization | **Free** | Paid |
| Size | 9 MB | 1 MB |
| Requires iOS | 15.0 | **13** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Myron L Company](https://appshunter.io/developer/885545010) | [Nitrio](https://appshunter.io/developer/321121189) |

## What reviewers say

### ULTRAPEN™ PTBTx™

[App page](https://appshunter.io/ios/app/ultrapen-ptbtx/id885545007)

This application transforms your iOS device into a powerful water quality measurement tool when paired with specific pocket testers. It offers wireless data logging, calibration tracking, and exportable reports for various water parameters.

**Highlights:** Wireless communication with pocket testers, Intuitive GUI for pairing and calibration, On-board database for measurements, Data export in .xls, .xlsx, .csv formats, Automatic calibration records, Supports conductivity, TDS, salinity, pH, ORP, and temperature

**Features:** macOS Compatibility

**In-app purchases:** none


### Solution Dilution Calculator

[App page](https://appshunter.io/ios/app/solution-dilution-calculator/id1353265965)

This utility app helps users calculate the precise volume of stock concentrate needed to create a diluted solution of a specific concentration and volume. It supports various concentration units and is designed for educational and research laboratory use.

**Highlights:** Dilution calculations, Supports mass/volume units, Supports weight/volume units, Ideal for labs and education, User-friendly interface

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

**In-app purchases:** none


## Frequently asked questions

### Is ULTRAPEN™ PTBTx™ free?

ULTRAPEN™ PTBTx™ is free to download, with no in-app purchases.

### Is Solution Dilution Calculator free?

Solution Dilution Calculator costs $2.99, with no in-app purchases.

### Which has better reviews, ULTRAPEN™ PTBTx™ or Solution Dilution Calculator?

Solution Dilution Calculator is rated higher. ULTRAPEN™ PTBTx™ averages 3.7 out of 5 from 3 ratings, while Solution Dilution Calculator averages 5.0 from 1 ratings.

### Do ULTRAPEN™ PTBTx™ or Solution Dilution Calculator have ads?

Neither ULTRAPEN™ PTBTx™ nor Solution Dilution Calculator shows ads.

### Which is updated more often, ULTRAPEN™ PTBTx™ or Solution Dilution Calculator?

ULTRAPEN™ PTBTx™ ships an update every 5 months, and Solution Dilution Calculator every 22 months. Most recently, ULTRAPEN™ PTBTx™ was updated on October 7, 2026 and Solution Dilution Calculator on October 15, 2026.

---

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