# telliSize vs Knock Knock Pros

The clearest difference is update cadence: Knock Knock Pros at weekly against telliSize's every 9 months. Knock Knock Pros also leads on iOS requirement (15.1 vs 27.0). On price, rating, 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.

On the App Store both sit at effectively the same score — 5.0 for telliSize against 5.0 for Knock Knock Pros. Both are backed by a comparable volume of ratings — 3 and 4 respectively.

telliSize ships an update every 9 months, Knock Knock Pros weekly. The most recent releases landed on November 2, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | telliSize | Knock Knock Pros |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (3 ratings)](https://appshunter.io/ios/app/tellisize/id1178730332/reviews) | [5.0 (4 ratings)](https://appshunter.io/ios/app/knock-knock-pros/id6465991587/reviews) |
| Number of ratings | 3 | **4** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 9 months | **Weekly** |
| Monetization | Free | Free |
| Size | 16 MB | 38 MB |
| Requires iOS | 27.0 | **15.1** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Intellihot](https://appshunter.io/developer/1073126287) | [Tim Sparks](https://appshunter.io/developer/1706824466) |

## What reviewers say

### telliSize

[App page](https://appshunter.io/ios/app/tellisize/id1178730332)

Quickly size water heater applications and generate project schematics, plumbing layouts, and submittals. Calculations are based on real-world test data and proven sizing methods.

**Highlights:** Water heater application sizing, Project schematics generation, Plumbing layout creation, Submittal package generation, Real-world test data calculations

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

**In-app purchases:** none


### Knock Knock Pros

[App page](https://appshunter.io/ios/app/knock-knock-pros/id6465991587)

Connect with skilled professionals for various home services, from plumbing and electrical work to cleaning and repairs. Easily book, track, and pay for services with a user-friendly interface and vetted providers.

**Highlights:** Wide range of services (196+ categories), GPS tracking for professionals, Easy and intuitive booking process, Vetted and trusted service providers, Flexible scheduling options, Secure in-app payments

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is telliSize free?

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

### Is Knock Knock Pros free?

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

### Which has better reviews, telliSize or Knock Knock Pros?

telliSize and Knock Knock Pros are both rated 5.0 out of 5 on the App Store, from 3 and 4 ratings respectively.

### Do telliSize or Knock Knock Pros have ads?

Neither telliSize nor Knock Knock Pros shows ads.

### Which is updated more often, telliSize or Knock Knock Pros?

telliSize ships an update every 9 months, and Knock Knock Pros weekly. Most recently, telliSize was updated on November 2, 2026 and Knock Knock Pros on November 3, 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.*