标签：#mobile

In this article, I describe the challenges and the design of a React Native real-time mobile beat-aligned playback system for iOS and Android. The system combines personalization with low-latency, and seamless navigation and was the result of careful analysis and experimentation to address strict mobile and network constraints as well as meet user expectations. By Vladyslav Melnychenko

Users judge a mobile app in the first few seconds, and they judge it harshly. A slow launch, stuttering scroll, or a device that runs hot will sink an otherwise good app faster than a missing feature. Performance isn't one metric — it's four distinct areas, each with its own causes and fixes. Here's how to keep all of them healthy. Startup time — the first impression Time from tap to usable screen is the metric users feel most. Every extra second measurably increases abandonment. The usual culprits are doing too much before the first frame: heavy synchronous work at launch, loading data you don't yet need, and oversized bundles. Fixes: Defer non-essential initialization until after the first screen renders Lazy-load features and screens instead of loading everything upfront Show a real first screen fast, then hydrate data — don't block on the network Trim your dependency footprint; every library adds to startup cost Rendering — kill the jank Smooth means hitting the device's frame budget (about 16ms per frame for 60fps). Dropped frames show up as stutter during scrolling and animation. The main causes are doing heavy work on the UI thread and rendering more than you need. Virtualize long lists so only visible rows render (FlatList, RecyclerView equivalents) Move expensive work off the main thread Avoid unnecessary re-renders — in React Native, memoize and keep render functions cheap Optimize images: right-sized, cached, and in efficient formats Memory — don't get killed The OS terminates apps that use too much memory, and users read that crash as your bug. Leaks and oversized assets are the main offenders. Watch for retained references, unbounded caches, and full-resolution images held in memory. Load and decode images at display size, release resources when screens unmount, and cap in-memory caches. Battery and network — the invisible costs Users blame the app that drains their battery even if they can't name why. The big drains are aggressive polling, chatty netwo

Even though they haven’t been officially announced yet, Samsung is giving you a chance to save some cash when you preorder what we’re expecting to be the brand’s updated Galaxy Z Fold phones. The next Galaxy Unpacked event will take place on July 22nd, 2026, and features the tagline “A new shape unfolds.” In addition […]

I'm building TrainWiz , a Flutter app that turns real exercise into a pet-raising game: you do squats or push-ups, your phone counts the reps, and a little creature levels up and evolves. The core technical problem sounds trivial and absolutely is not: count reps from the camera, on-device, without uploading a single frame. Here's what broke along the way, and what finally worked. Why on-device Two reasons: privacy and latency. A fitness camera that streams your body to a server is a non-starter for most people, and rep feedback has to feel instant or the whole "game" loop dies. So everything runs locally with tflite_flutter + an on-device pose model — no footage ever leaves the phone. Naive attempt #1: joint-angle thresholds The obvious approach: track the knee angle, count a rep when it dips below X° and comes back up. // looks fine in a demo, dies in the real world final kneeAngle = angleBetween ( hip , knee , ankle ); if ( ! _down && kneeAngle < 100 ) _down = true ; if ( _down && kneeAngle > 160 ) { reps ++ ; _down = false ; } It demos beautifully. Then real users prop the phone on the floor, stand at an angle, and it falls apart. The trap: a phone camera gives you 2D pose. A "120° knee angle" flattens completely depending on where the camera sits — the same squat reads as 90° or 150° purely from perspective. Lifting to 3D via the model's z doesn't save you either; monocular z is noisy enough that the angle jitters across your threshold and double-counts. Naive attempt #2: a "body-line" gate Next idea: figure out which exercise you're doing so I can pick the right signal. Standing (squat) vs. horizontal (push-up) should be easy — just check if shoulder, hip and heel form a straight line, right? Wrong, again for the 2D reason. In a real push-up shot from the front-corner, shoulder–hip–heel are not collinear on the image plane — perspective bends them. I gated push-up counting on "body is a straight line" and it would just... stop counting mid-set. Nothing is more

Google's upcoming Pixel lineup might cost more than last year's. A report from Dealabs spotted by 9to5Google suggests that Google could raise the starting price of its 41mm Pixel Watch 5 to $399, while adding LTE could bump the price to $499. That's a $50 jump from the base Pixel Watch 4, which starts at […]

A key delay from a state agency means robotaxi rides in the company’s new Ojai vehicle might be free for a few more months.

Samsung has announced that its next Galaxy Unpacked launch event will be held on July 22nd, with the tagline: "A new shape unfolds." It's long been rumored that Samsung is about to expand its foldable phone line to a third format, with a shorter and wider version of its big book-style foldables, to match Huawei's […]

The help button is the most important button in your delivery app that your QA team almost never...

Nothing is shaking up the branding of its cheapest phones, following up last year's Phone 3A Lite with a new Phone 4B. Combining design elements of the 4A and 4A Pro, it follows Nothing's previous cheaper handsets in skipping the US market. The company already uses the "A" branding to market its cheaper tier of […]

In 2008, Richard Thaler and Cass Sunstein needed an example simple enough to explain the whole of economic theory from a single application. They used a cafeteria menu. By moving the fruit to eye level and sending the fries to the periphery, they demonstrated that a slightly adjusted environment could convince thousands of students to make healthier choices. No one is stopped from choosing fries and the fries-loving student still chooses fries. But the undecided student chooses the apple, simply because it is now right in front of him. In 2017, Thaler was awarded the Nobel Prize in Economics for his body of work, including the development of “The Nudge Theory” with Sunstein. In the years that followed, product teams building mobile applications have taken to referring to any call-to-action on-screen as a nudge. The design of an effective nudge There are two requirements for a nudge to work reliably. The user should have an apparent desire for the thing they are being nudged toward, and the nudge should appear at the moment when this desire is at its peak. The first requirement ensures the user has a mental model of the target action, meaning they understand roughly what they are supposed to do. The second requirement serves to remove any extraneous context, ensuring the nudge does not fail due to poor timing. A checkout confirmation modal shown straight after launching the application will fail miserably as a nudge. The desire to checkout is non-existent at the launch moment, and the context of the action has little to do with the action itself. A tooltip shown after a specific number of unsuccessful attempts to checkout after viewing the cart, however, is a nudge. It has the desired behavior and the right timing. Why the difference shows up in the numbers In the example with Duolingo, the product team has effectively used the framing of an existing streak as a reference point for the next level of engagement. The players who saw streak-based progress notifications

The 300-mile Torcal arrives in September, but considering what's come before with Ferrari, Porsche and Mercedes, has the company timed its EV entry right?

Privacy isn't a checkbox. It's not a statement in your terms of service. It's not a toggle in your settings app. Privacy is architecture. And most apps get this backwards. The Architecture Test Here's a simple test for any app that claims to be "privacy-first": If your server goes down, can anyone still access user data? If the answer is yes, your privacy is a policy question — not a technical guarantee. You've built a system where trust in the company replaces trust in the code. Every photo cleaner that uploads your images to a server has already failed this test. The moment data leaves your device, privacy becomes something you promise rather than something you enforce . What On-Device Processing Actually Means When we built Swipe Cleaner, we made one architectural decision that defined everything else: zero data leaves the phone . This means: No cloud processing of photos No API calls that transmit image data No server-side storage of any kind Every scan, every classification, every cleanup happens locally The app is 4.7 MB. That's it. There's nothing to hide because there's nowhere to hide anything. Why Architecture Beats Policy Companies spend millions on legal teams writing privacy policies that their architecture contradicts. They collect data "to improve the service" while the service could have been designed to not need that data in the first place. Policy-based privacy Architecture-based privacy "We promise not to misuse your data" "We can't misuse data we never have" Requires ongoing trust Verifiable by anyone Can change with an update to ToS Requires rewriting the entire app Compliance-driven Principle-driven The Trust Problem Here's what I've learned building privacy-focused tools: users can't verify your privacy policy. They can't audit your servers. They can't check if you're actually deleting their data after processing. But they can verify that an app never sends their photos anywhere. They can check network traffic. They can inspect the binary. Tha

The Ikko MindOne Pro is delightfully small. I keep calling it a square phone, which isn't quite right; the screen is square, but the phone itself is slightly rectangular. The camera flips up so you can use it for selfies - you can even open it partway to use as a stand or a kind […]

It happened during a quiet, solemn moment in a community prayer hall. I was sitting in the third row, reflecting, when suddenly, a high-pitched ringtone shattered the silence. It wasn't my phone, but the ripple effect of embarrassment was immediate. Everyone looked around, shifting uncomfortably. That collective tension is something we have all felt—a moment of human error that technology should have intercepted. I looked at my own device, feeling the familiar anxiety of whether I had remembered to flip the physical silent switch. It was then that I decided to stop relying on my own memory. We live in an era of hyper-connected devices, yet the most basic context-awareness—knowing where we are and how our phone should behave—remains manual. I found myself constantly toggling between 'Normal' and 'Silent' modes at the library, the office, and the gym. If I forgot, I was the person disrupting a meeting. If I remembered to mute it, I inevitably forgot to unmute it, missing urgent calls from family for hours. The existing solutions were either too bloated, requiring invasive cloud permissions, or they simply failed to trigger reliably when the screen was off. I needed a solution that was local, predictable, and battery-conscious. Building Muffle started with the realization that I had to master the GeofencingClient API without draining the user's battery. The primary challenge wasn't just triggering an event; it was doing so while the device was in a deep sleep state. I initially experimented with a standard LocationManager approach, polling GPS coordinates at set intervals. That was a disaster. It kept the radio active, pinged the GPS satellites constantly, and decimated the battery life in under four hours. It was an immediate non-starter for a production-ready application. I pivoted to the Geofencing API provided by Google Play Services, which leverages the fused location provider. This is significantly more efficient because the system handles the batching and hardwa

개발 역량이 없어도 외주 개발사의 진행 상황을 명확하게 파악하고 피드백을 줄 수 있다. 필요한 건 기술 지식이 아니라, 올바른 협업 구조다. 이 글은 비개발자 제품 관리자가 바로 적용할 수 있는 투명한 피드백 루프와 점검 방식을 소개한다. 외주 개발에서 비개발자가 소외되는 이유는 무엇인가? 외주 개발사와 일을 시작하면 처음 며칠은 소통이 활발하다. 요구사항 정리, 계약, 착수 미팅까지는 순탄하다. 문제는 그 이후다. 개발이 시작되면 대화의 언어가 바뀐다. "API 연결 중", "백엔드 스키마 설계 단계", "프론트 컴포넌트 분리 작업"처럼 전공자가 아니면 체감하기 어려운 표현들이 보고서를 채운다. 이 상태에서 비개발자가 할 수 있는 질문은 사실상 하나뿐이다. "잘 되고 있나요?" 그리고 돌아오는 답도 하나다. "네, 잘 되고 있습니다." 이 구조는 어느 개발사가 나쁜 의도를 가져서 생기는 문제가 아니다. 개발자는 기술 언어로 사고하고, 비개발자는 결과와 흐름으로 사고한다. 이 두 언어 사이에 다리가 없을 때 소외가 생긴다. 그리고 이 소외는 감정의 문제가 아니라 실질적인 리스크다. 방향이 틀어진 채 몇 주가 흐르면, 다시 맞추는 비용은 처음보다 훨씬 커진다. 비개발자가 개발 과정을 직접 점검할 수 있는 구조가 필요한 이유가 여기 있다. 비개발자가 진행 상황을 파악할 수 있는 협업 구조란? 투명한 협업 구조는 "보고를 더 자주 받는 것"이 아니다. 받는 정보의 언어와 형식을 바꾸는 것이다. 포텐랩은 매주 진행 상황을 공유하는 주간 피드백 루프를 팀 표준으로 운영한다. 이 루프의 핵심은 세 가지다. 무엇이 완료됐는가 : 이번 주에 실제로 만들어진 것, 확인 가능한 것. 다음 주에 무엇을 만드는가 : 다음 단계에서 기대할 수 있는 결과물. 막힌 것이 있는가 : 결정이 필요하거나 확인이 필요한 사항. 이 세 가지가 매주 비개발자도 읽을 수 있는 언어로 정리된다면, 소통 구조는 이미 절반 이상 해결된 것이다. 기술 용어 없이 "로그인 화면 완성, 다음 주엔 상품 목록 화면 작업"이라고 쓸 수 있다면, 비개발자는 지금 어디쯤 왔는지 감을 잡을 수 있다. 주간 피드백 루프를 실제로 설계하는 방법 주간 루프가 형식적인 보고에 그치지 않으려면 구조가 있어야 한다. 아래는 포텐랩이 프로젝트마다 적용하는 주간 피드백 사이클의 구성이다. 1단계 — 주간 업데이트 문서 공유 매주 정해진 요일에 개발팀이 업데이트 문서를 공유한다. 이 문서에는 완료된 기능, 다음 주 작업 항목, 그리고 결정이 필요한 사항이 포함된다. 형식은 슬랙 메시지든, 노션 페이지든 팀이 합의한 채널이면 된다. 중요한 건 형식보다 주기와 언어다. 매주 같은 날, 비개발자가 읽을 수 있는 언어로. 2단계 — 화면으로 확인 가능한 결과물 공유 텍스트 보고만으로는 실제로 무엇이 만들어졌는지 체감하기 어렵다. 그래서 주간 업데이트에는 화면 캡처, 동영상 클립, 또는 테스트용 링크가 함께 제공된다. "로그인 기능 완료"라는 문장보다 실제 작동하는 화면을 보는 것이 훨씬 구체적인 판단 근거가 된다. 3단계 — 비개발자가 직접 테스트하는 시간 개발팀이 보여주는 것만 보는 게 아니라, 비개발자가 직접 써보는 단계가 필요하다. 이 과정에서 "버튼이 너무 작다", "이 순서가 직관적이지 않다" 같은 피드백이 나온다. 기술 지식이 없어도 할 수 있는 피드백이고, 이런 피드백이 제품의 방향을 바로잡는다. 4단계 — 다음 주 작업 범위 합의 이번 주 결과를 확인한 뒤, 다음 주에 무엇을 만들지 함께 정한다. 이 단계에서 비개발자는 우선순위를 조정할 수 있다. "이 기능보다 저 기능이 먼저 필요하다"는 판단을 매주 할 수 있는 구조다. 우선순위는 비개발자가 가장 잘 아는 영역이다. 비개발자가 개발 진행 상황을 점검하는 실질적인 기준은? 개발 진행 상황을 평가할 때 기술적 판단을 할 필요는 없다. 다음 세 가지 기준으로 충분히 점검할 수 있다. 점검 항목 확인 방법 좋은 신호 주의가 필요한 신호 완료 결과물 화면 또는 테스트 링크로 직접 확인 매주 눈에 보이는 결과물이 있음 텍스트 보고만 있고

Where's the Trump phone? We're going to keep talking about it every week. One year on, our phones have finally arrived. 12 months, 16 days, 21 hours, and 54 minutes after I first heard about Trump Mobile's T1 Phone 8002 (gold version), I'm finally holding one in my own hands. That's right, The Verge's Trump […]

Announced at WWDC 2026, the latest SwiftUI release brings a new Document protocol for efficient disk access and snapshot-based updates, along with improved APIs for reordering items in lists, grids, and sections. In addition, it expands presentation features, such as swipe actions on any view, better AsyncImage caching, and lazy state initialization for Observable types to boost performance. By Sergio De Simone

Slate is the latest automaker to transition to lower-cost batteries perfected in China, driven in part by the repeal of EV tax credits that required materials to be sourced domestically.

Testing a food delivery app is hard. Testing an on-demand logistics app is harder. Food delivery has...

T-Mobile wants Broadcom to keep supporting its VMware perpetual licenses.