Prezence is a native iOS focus app built by Mobilions to help people stay off distracting apps during deep-work and study windows. It pairs timed focus sessions with app and category blocking, a live countdown timer, and an NFC tag unlock that adds a deliberate, physical step to ending a session early.
What Prezence is and what Mobilions built.
Prezence is a focus and screen-time companion for iOS. The core idea is simple: a user starts a timed focus session, and during that session the apps and categories they want to avoid are blocked, keeping their attention on the task in front of them.
Mobilions built Prezence as a native iOS application in Swift. The feature set centers on four capabilities that together turn "I want to focus" into an enforced, time-boxed routine on the device. These are timed focus sessions, app and category blocking, NFC tag unlock, and a live countdown timer.
The NFC tag unlock is the differentiating detail. Rather than letting a user tap away a block with a single button, ending or bypassing a session requires scanning a physical NFC tag, adding friction that discourages impulsive unlocking.
Key facts about the product and engagement.
Fitness / Health (Health & Fitness category)
iOS (native, Swift)
The services Mobilions provided to build this app.
The core technologies behind the app.
The problem space this app addresses.
Wanting to focus and holding that focus are different things, and the gap between them is where a study or deep-work window is usually lost. Prezence exists to close that gap as a focus and screen-time app for iOS, turning an intention into a time-boxed routine the device enforces by blocking the apps and categories most likely to pull attention away. The difficulty is that a block a user can lift the instant it becomes inconvenient stops being worth trusting, so the exit has to cost something without being impossible.
On iOS an app cannot police other apps directly, so every block has to be expressed through the platform's own screen-time and restriction capabilities, whose behaviour and permissions are set by Apple's frameworks and review guidelines rather than by the app. Core NFC adds a second problem, because a tag read is a user-initiated action that can be cancelled or simply not complete, and the session has to stay in a known state either way. The countdown also has to report the same remaining time whether or not Prezence is the app on screen.
How a focus app like this is typically built.
Two constraints shaped Prezence early. The first was behavioural: the weakest point of a focus app is its exit, because a block a user can lift with an on-screen button is one they lift the moment attention wanders. The second was platform-level, since enforcement belongs to the system rather than the app, through the iOS screen-time and restriction capabilities, and Apple's review guidelines set limits on what a blocking app may do. Both findings pointed to a native Swift build with direct access to those APIs and a physical NFC tag on the exit.
Prezence is put together as four layers inside a single native Swift app. A session layer owns the chosen duration and the state of the run, and it is the only part allowed to declare a session over. A restriction layer translates the apps and categories a user has selected into the iOS screen-time and restriction capabilities, so the block is enforced by the platform rather than by the app watching from outside. A Core NFC layer guards the exit, reading the physical tag before the session layer will end or bypass a block, while a native iOS UI layer carries the session controls and the live countdown timer.
The Prezence build was carried out screen by screen along the focus session flow. A picker lets the user choose the apps and categories to hold back, a start screen sets the duration, and the in-focus screen carries the live countdown. The NFC path was built as two states, a scan prompt followed by a scan confirmation, so the user knows whether the tag has been read. The interface was kept plain and low-distraction, and the feature set was designed to align with Apple's review guidelines ahead of App Store submission.
Notable build choices for this app.
A confirmation dialog can be dismissed without leaving the chair, so the exit in Prezence was moved off the screen entirely and onto a physical object. Core NFC handles the read, and because the phone and the tag have to be brought together, ending a session early becomes a decision rather than a reflex. Delays and confirmations were the softer alternatives and they do not carry the same weight.
App blocking and tag reading both live in device-level APIs, and Swift reaches the iOS screen-time, restriction and Core NFC capabilities directly, with no bridge in between. A cross-platform layer would have added a dependency on the exact part of the system Prezence relies on most, so the team accepted a single-platform build to keep that access first-hand.
Naming every distracting app one by one leaves gaps, and anything left off the list stays open during a session. Blocking at category level alongside individual picks lets a user hold back a whole class of iOS apps in one choice, which keeps the selection step in Prezence short and the block harder to work around.
Why the stack fits this kind of app.
Swift is the native language for iOS, giving direct access to the platform's screen-time, restriction, and Core NFC APIs that a blocking-and-unlock app of this type depends on.
The app's core capabilities, as delivered.
Users start a focus session for a set duration. The session defines the window during which distractions are held back, turning an intention to focus into a concrete, time-boxed block.
During a session, selected apps and whole categories of apps are blocked on the device, so the most common sources of distraction are unavailable until the session ends.
Ending or bypassing a session requires scanning a physical NFC tag. The extra physical step adds intentional friction, making it harder to abandon focus on impulse.
A live countdown shows how much focus time remains, giving the user constant, at-a-glance feedback on their progress through the session.
A look at the product across screens.
If you need a focus, screen-time or device-restriction app with app blocking, timed sessions and NFC, let us show you how we would build it.
In their own words, Mobilions' clients describe fast delivery, clear communication, and senior, trustworthy engineering.
Great experience working with this team. They completed the development work quickly and efficiently without wasting time. Communication was clear and consistent, they understood the requirements well, gave smart suggestions, and delivered exactly as discussed. I'd highly recommend them to anyone looking for a reliable, fast, and skilled app development team.
We worked with Ankit, Mayur, and Tushar to build the first version of Baba Hebrew for iOS and Android, and they delivered super fast. The team was responsive, reliable, and efficient, taking the idea from zero to a working app in record time. I'd recommend them to anyone who wants to get an MVP live quickly.
Tushar and Ankit did an outstanding job developing our native iOS (Swift) and Android (Kotlin) apps. They were efficient, responsive, and technically strong throughout. Thanks to their work, we launched successfully and gained over 1,000 users in the first 30 days. Highly recommend this team for quality mobile app development.
It was a wonderful experience working with Tushar, Ankit, and their team. They built a great mobile app for me and truly brought my vision to life. What stood out was not just their technical skill but their attitude: always positive, solution-oriented, and incredibly patient. They went above and beyond at every step, finding creative workarounds and staying committed even when things got challenging. Extremely professional and trustworthy. I would absolutely hire them again.
Common questions about building a focus or screen-time app.
It depends on scope. A focused MVP with timed sessions and basic blocking is faster to ship than a full product with NFC unlock, scheduling, and analytics. We scope a timeline after a short discovery call once your must-have features are clear.
Yes, within Apple's rules. iOS exposes screen-time and restriction capabilities that let an app limit selected apps and categories. The exact behavior is governed by Apple's frameworks and review guidelines, which we design around from the start.
An NFC tag adds a deliberate physical step to ending a session. That friction discourages impulsive unlocking, which is often the point of a focus tool. It is one of several "commitment" mechanisms we can build, alongside delays or confirmations.
Apps that lean heavily on device-level capabilities like app blocking and NFC are usually best built native, where access to the relevant platform APIs is most direct. We will recommend an approach based on your features and target platforms.
Cost tracks scope, platforms, and integrations. We give a written estimate after discovery so you see the cost against a specific feature set rather than a generic range.
Yes. Monetization such as subscriptions, paid tiers, or premium features can be designed in from launch or added later. We will flag the implications for your store listing and architecture early.
Yes. We support preparing the build, metadata, and privacy details, and we design features to align with Apple's review guidelines so submission goes smoothly.
Yes. We regularly pick up from a concept, a feature list, or an existing codebase, assess what is there, and continue the build from that point.
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