# BMS Tool vs i

The clearest difference is in-app purchases: i at none against BMS Tool's 1. i also leads on ads (none vs shown) and iOS requirement (13.0 vs 15.0). BMS Tool's advantage is device support (4 vs 2). On price and update cadence there is nothing between them.

Both are free to download. BMS Tool sells 1 one-off in-app purchase. i asks for nothing beyond the download.

BMS Tool ships an update every 2 months, i every 6 weeks. The most recent releases landed on October 29, 2026 and October 28, 2026 respectively.

## The numbers

| Metric | BMS Tool | i |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.9 (7 ratings)](https://appshunter.io/ios/app/bms-tool/id1511343379/reviews)** | — |
| Number of ratings | **7** | — |
| Positive reviews | 71.4% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 2 months | **Every 6 weeks** |
| Monetization | Free with in-app purchases | — |
| Size | 20 MB | 25 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | **iPhone, iPad, iPod, Apple Watch** | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [e77code GmbH](https://appshunter.io/developer/1375405425) | [Grandfar](https://appshunter.io/developer/1811247874) |

## What reviewers say

### BMS Tool

[App page](https://appshunter.io/ios/app/bms-tool/id1511343379)

Monitor your battery management systems via Bluetooth. Supports multiple BMS types including Liontron, XiaoXiang, ANT, and Wattstunde. Offers a screen always-on mode and macOS compatibility.

**Highlights:** Screen Always ON mode, Multiple BMS support, Liontron BMS read-only, XiaoXiang BMS read-only, ANT BMS read-only, Wattstunde LiFePo4 read-only, macOS support

**Features:** macOS Compatibility, Apple Watch app

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $3.99 | one-time |


### i

[App page](https://appshunter.io/ios/app/i-grandfar/id6745197238)

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

**In-app purchases:** none


## Frequently asked questions

### Is BMS Tool free?

BMS Tool is free to download, with in-app purchases available.

### Is i free?

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

### Do BMS Tool or i have ads?

BMS Tool shows ads; i does not.

### Which is updated more often, BMS Tool or i?

BMS Tool ships an update every 2 months, and i every 6 weeks. Most recently, BMS Tool was updated on October 29, 2026 and i on October 28, 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.*