Blogs
Practical ideas for better mobile apps. Design decisions, iOS and Android engineering, and lessons from connected products.
iPhone Duo App Design: What to Change in Your iOS App
Updating an iOS app or starting a new one? Explore iPhone Duo layouts, common UI issues, side controls and a practical app review checklist.
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iPhone Duo App Design: What to Change in Your iOS App
Updating an iOS app or starting a new one? Explore iPhone Duo layouts, common UI issues, side controls and a practical app review checklist.
The world's best-selling Bluetooth health device is a disposable
Nobody tracks BLE health device shipments. On radios shipped per year the answer is Abbott's FreeStyle Libre: about 200 million. The radio is disposable.
How Bluetooth Low Energy took over Bluetooth
A Viking king, a trademark search that ran out of time, and the 22.5 milliseconds that made BLE inevitable. The history of the radio that took the name.
Your Android BLE connection fails with GATT error 133
GATT error 133 is not an error code so much as the absence of one. What status 133 means inside Android's stack, and the failures that produce it.
The readings your Bluetooth health device app never collected
Health devices record measurements while the phone is away and hand them over through the Record Access Control Point. Notifications alone will lose them.
What it actually takes to launch your own health band
Sourcing, certification, the claims you cannot make, and the app the factory will not build. A realistic bill for putting a wearable on the market.
Your BLE scan throws a SecurityException on Android 12 and not on 11
Android 12 split the Bluetooth permissions and most crash reports come from one missed runtime request. What changed, and what neverForLocation costs you.
You called setNotifyValue and no notifications arrive
Subscribing to a characteristic succeeds and nothing comes back. Six causes on iOS, ordered by how often they turn out to be the one.
Why your BLE writes silently fail on iOS
Writes that return no error and never reach the device. Five causes, and why write-without-response drops data the moment you stop checking.
Why the iOS Bluetooth pairing dialog never appears
Your peripheral requires bonding but iOS never prompts. Why the dialog is triggered by a characteristic rather than by connecting, and how to force it.
What a CoreBluetooth developer costs in the US, UK and Australia
Rate bands for BLE specialists in three markets, why the UK quotes days instead of hours, and the number that matters more than either.
How long BLE app development takes, and why certification sets the date
Agency pages say four to twelve weeks. That is the app. In the US, UK and Australia the launch date is usually set by radio approval instead.
CoreBluetooth state restoration, and why your peripheral drops when the app suspends
Apple's guidance on state restoration is archived and dated 2013. Here is what actually keeps a connection alive across suspension and termination.
ESP32 BLE shows up on Android but not on iOS
Android scans permissively and iOS does not. Four differences account for nearly every ESP32 device that is invisible to an iPhone.
Hiring a freelance CoreBluetooth developer in India
What makes a cross-border BLE engagement work: who already owns the test hardware, how blocking firmware questions get answered, and what the specialist premium buys.
Before you hire for an iOS BLE integration, check these five things
Most BLE integrations that go badly were not built badly. They started before the project was ready, and the app developer absorbed the delay.
Freelance iOS and Android MVP pricing in Europe
What the rates actually are across Europe, how they compare against India and the US, and how to read a quote instead of just comparing numbers.
Bluetooth app development cost: how to estimate yours
Published ranges run from $10k to $150k, which helps nobody. Why BLE breaks normal estimation, and a worksheet that produces a number you can defend.
Hiring a firmware and Bluetooth app developer
One role or two, what a generic iOS developer will miss, and the screening questions that separate people who have shipped BLE hardware from people who have read about it.
You vibe-coded an app. Here's what breaks when you try to ship it.
What goes wrong when an AI-built prototype meets the App Store, how to triage it in a day, and how to tell a fixable codebase from a rewrite.
iOS in 2026: what is mandatory, what is optional, and what each one costs
The April SDK deadline already changed how your app looks. What iOS 26 and 27 actually require, and what is worth paying for.
Why your CoreBluetooth scan finds nothing on a real device
Four reasons a BLE scan that works in the simulator returns an empty list on real hardware, and how to tell them apart.
Designing BLE OTA updates that survive a dropped connection
A firmware update over Bluetooth will be interrupted. The design question is what happens on the next connection, not how to prevent it.
What shipping hardware companion apps teaches you about scope
Notes from building iOS apps that talk to physical products: where the schedule goes, and what to fix early.