# Battery Monitor BM2 — user reviews > 226 indexed App Store user reviews of Battery Monitor BM2 by Shenzhen Leagend Optoelectronics Co., Ltd., rated 4.10/5 from 59 ratings. - Source: https://appshunter.io/ios/app/battery-monitor-bm2/id1115492033/reviews - App overview in markdown: https://appshunter.io/ios/app/battery-monitor-bm2/id1115492033.md - Rating breakdown: 5★ 33 · 4★ 14 · 3★ 4 · 2★ 3 · 1★ 5 ## What do users think of Battery Monitor BM2? Overall sentiment: neutral **Pros** - 👍 Multi-device support - 🚀 Useful monitoring app - 📈 Good historical data - 🔋 Accurate battery readings **Cons** - 🐛 Connectivity issues - 🔋 High data usage - 🔍 Limited customization options - 💤 Syncing problems **Commonly reported bugs** - App crashes on certain screens - Firmware update not working - Inconsistent battery percentage readings - Compatibility issues with iOS 13 **Most requested features** - Add CarPlay support - Ability to export data - More battery type options - Remote monitoring capability ## Newest reviews (17 of 226) ### 4/5 — Bluetooth distance is short *2026-07-13* The device actually connected easily and works quite well. My problem is I have to be very close to the car for it to connect to the Bluetooth. Not sure if this is this particular apps Ben issue or if it is just how Bluetooth is. ### 2/5 — No lithium *2026-06-25, version 3.4.2* There should be better support for lithium batteries ### 3/5 — Poor Connectivity *2026-03-01* Cannot connect even a few feet away in the house. Apparently no way to work with Home Assistant or BT repeaters. So I was never notified of a low battery. That was the purpose. ### 4/5 — Multi Car Uses *2026-01-24* I have 4 of these installed on two classic cars and two electric cars. Works great. Very nice to monitor your charging system on the fly. The app need a way to rename the devices. ### 4/5 — CarPlay App or Widget would be great *2025-12-22, version 3.4.2* CarPlay App or Widget would be great ### 3/5 — Lescars *2025-12-18* Leider funktioniert die App nicht mehr mit den neuen Wächtern von lescars, wurde irgendetwas geändert? ### 3/5 — Traveller *2025-11-24, version 3.4.2* I have 1 battery for driving and 2 (classed as 1 as it is linked) for RV life…..BUT I CAN NOT VIEW BOTH BATTERIES AT THE SAME TIME !!! Frustrating ! ### 3/5 — Need more settings *2025-07-06, version 3.4.2* I have a question about low limit measurement voltage level. Now is the range from 9-15 only. The input voltage is from 6V. is it automatically range, when lower values will occur? It is possible set lower limit (2V) by customer in next version ? ### 3/5 — App打不開 *2025-06-25, version 3.4.2* 已經好幾年用IOS系統都打不開APP了，是停用了嗎？ ### 4/5 — Good monitoring app *2025-06-18, version 3.4.2* Been using this for several years and works as expected on an iPhone 13 ### 4/5 — G *2025-02-12, version 3.4.1* Trochę mało rozbudowana, tylko podstawowe rzeczy są. ### 4/5 — Issues with multiple vehicles. *2025-01-15* Have used this app for almost a year and quite appreciate it’s usefulness, but have a real issue trying to switch screens between installed hardware in different vehicles. I installed the sensor unit in two vehicles but cannot seem to get the app to switch between them. ### 4/5 — Possible current draw issue? *2024-06-15* I’ve had the BM2 attached to my EV6’s battery for over a year now, since I had the car towed in due to ICCU failure. It seemed to work well, but today while I was listening to the radio in the car while waiting for my wife at a hair appointment, I got a warning screen: “Battery low, come to a safe stop.” I checked the app, it said the voltage was down to 6.5 volts! So I got a guy to jump start me with his 12V battery cables, took my wife to lunch and then home, then onto my local dealer. The manager said they tested the battery, it was fine; the problem was the 3rd party voltage monitor. Its power draw, he said, could be enough to drain the battery dead. At 1.5mA, does that make any sense? ### 4/5 — Improvements *2024-04-24, version 3.4.1* Add the ability to export data to a file. ### 3/5 — Insufficient warning *2024-04-02, version 3.4.1* I connected it directly to the motorcycle battery, but there was no warning even when it reached 11 volts. Also, just recently it got stuck on the startup screen and I couldn't do anything until I reinstalled the app to restore it. ### 2/5 — App tracks data *2024-03-05, version 3.4.0* This app collects tracking data and accessed a website with dangerous urls. Tried turning off the location service for this app but did not fix the issue. Very disappointing considering the hardware works well. ### 4/5 — Excellent Product *2024-02-02* The whole thing works really well on my iPhone 15 and iPad. The range isn’t great though. Also, I would like to be able to export the data so I can analyse it in Excel. It would also be good if I could monitor the battery remotely, via the Internet. However, it works and it works well for the functions it is programmed to perform. ## Most critical reviews (10 lowest-rated) ### 1/5 — Synchronizing Data *2026-03-03* The majority of the time when I open this app it connects to Bluetooth, and then starts synchronizing data and the synchronization never ends. While the is doing that it is not usable, it’s like it’s froze up. This has been going on for a few years now rendering the app useless. ### 1/5 — Keine Verbindung *2025-09-19* Seid IOS26 verbindet sich Gerät nicht mehr mit Handy… ### 1/5 — Bluetooth *2024-12-14* Le Bluetooth ne fonctionne pas déconnecté.une mise à jour du logiciel est nécessaire au plus vite. Merci ### 1/5 — Nicht für LiFePo *2024-11-01* Laut Beschreibung auch für PV Anlagen, aber es funktioniert nicht. Man kann die Batterie Zustände zwar einstellen, aber die App zeigt dennoch nur Werte für Bleiakkus an. ### 1/5 — Doesn’t do what it shows *2024-08-28, version 3.4.1* I wanted an app specifically for the percentage of battery. The screen shots show it, but the actual app doesn’t. This is the only thing I bought the Bluetooth monitor for!! I wrote an email / contacted app support and got no reply. Not impressed. ### 1/5 — Non ci siamo *2024-07-08, version 3.4.1* Non si collega piu al bluetooth e l’assistenza non risponde ### 1/5 — Perimeters *2024-05-27, version 3.4.1* Set Custom perimeters to 100% for 12.5 volts. But the settings don’t save at 12.5 monitor say 67% contacted the developer but got no reply ### 1/5 — Nothing great *2024-04-14, version 3.4.1* I have had mine while now and have to say it has added no value. Says my battery is at 34% but hasn’t sent me an notifications, even though set up. Just doesn’t feel like it is accurate. ### 1/5 — Android Head Unit *2024-01-23, version 3.4.0* I installed app years ago on phones and my cars head unit. It works on phones but NOT on my android head unit. I just noticed there it list BM2 wanbaolu as the developer! I uninstalled app then reinstalled and it still in not connect via Bluetooth. But my phone does. I want to use my head unit instead of phone on this vehicle. Everything else sees Bluetooth but not this app on this unit!! Not happy. ### 1/5 — Not downloading *2023-11-22, version 3.4.0* I have just bought the BM2 monitor and the app won’t download. Waste of money. ## Most praised reviews (10 highest-rated) ### 5/5 — Jest okej *2025-06-15, version 3.4.2* Spoko aplikacja, czysto i przejrzyście. Po pol roku uzytkowania nie doswiadczylem zadnych bug-ów czy czegokolwiek. ### 5/5 — To JohnTheReed *2025-04-19* I’ve had BM2 on my Niro EV for three years and never had a problem with battery drain on the still OEM battery. I think you are right to question the dealer who squawks a miliAmp draw. ### 5/5 — Нужен экспорт данных *2024-12-14, version 3.4.1* Хорошее приложение, наглядно показывает урони заряда АКБ. Просьба сделать возможность экспорта данных в виде файла для анализа на компьютере ### 5/5 — Battery monitor works as advertised. *2024-01-31* The only down side to this monitor is that the Bluetooth connectivity distance is very limited. Otherwise it does a great job of tracking and storing the battery voltage history. ### 5/5 — What a great app and tool *2023-11-05* I have 9 batteries that get monitored by this app. What a great piece of mind. Thanks again ### 5/5 — Great but 2 fixes please!! *2023-10-10* I am quite happy with this app. One major bug bear is that it tries to ‘connect’ while viewing the graphs sideways. Please can you fix this! And second is that I need to export the raw data ideally as a csv. Can you please add this function. ### 5/5 — Excellent and accurate *2023-08-02* Have used this for a couple of years with iPhone 12pm max and has been extremely accurate and useful with plenty of good notifications etc ### 5/5 — Noice *2022-07-12, version 3.3.5* Do far so good ### 5/5 — BM2 *2022-04-21, version 3.2.3* Jest dobrze :) choć zawsze mogłoby być lepiej. Czekam na rozwój aplikacji. ### 5/5 — Excellent and prompt response from the developers *2022-04-11* I love this app unfortunately the recent v3.2.0 & 3.2.1 updates crashed constantly usually when synchronising data on both my iPads I contacted the developer and within a few hours they released version 3.2.2 which fixed the problem. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-18.*