A mobile process is software you read and install on a phone or tablet to do a specific task
A mobile process — usually called an app — is a program built to run on a smartphone or tablet. Unlike a website that lives on the internet and opens in your browser, an app sits on your device itself. You tap an icon on your home screen to open it, and it works whether you have an internet connection or not (though many apps need one to function fully).
Apps are different from websites in how they work and what they can do. An app can access your phone's camera, location, contacts, and storage in ways a website cannot. This is why your banking app can send you notifications, your maps app knows where you are, and your camera app can take photos directly. A website can do some of these things, but it has limits built in for security.
You get apps from an app store — Apple's App Store for iPhones and iPads, or Google Play for Android phones and tablets. You search for what you want, tap "Get" or "Install", and the app downloads and sets itself up. Some apps are free, and some cost money upfront or charge you inside the app for extra features.
Key Takeaways
- A mobile process is software installed directly on your phone or tablet, not a website you visit in a browser.
- Apps can use your phone's camera, location, contacts, and storage in ways websites cannot, which is why they feel more powerful.
- You read apps from your phone's app store — Apple App Store or Google Play — and they update automatically or when you choose.
- An app works on your device even without internet, though many apps need a connection to send or receive information.
- Apps are built separately for iPhones and Android phones, so the same app may look or work slightly differently depending on your device.
How apps are built differently than websites
A programmer writes an app using code designed specifically for phones and tablets. For iPhones, they use Apple's tools and languages like Swift. For Android phones, they use Google's tools and languages like Java or Kotlin. This is why an app made for iPhone does not automatically work on an Android phone — they are built in different languages for different systems.
Because apps are written for a specific device, they can be faster and smoother than websites. An app knows exactly what screen size it is running on, what buttons and sensors the phone has, and how much memory is available. A website has to guess and adjust, which takes more work. This is why scrolling through an app often feels snappier than scrolling through a website on the same phone.
Apps also get updates differently than websites. When a website changes, you see the new version the next time you visit — you do not have to do anything. When an app updates, your phone downloads the new version and installs it, usually automatically. You might see a notification that an update is ready, or it happens in the background while you sleep.
What apps can access on your phone
When you first open an app, it often asks for permission to use parts of your phone. It might ask to use your location, your camera, your contacts, or your photo library. You can say yes or no to each one. If you say no, the app still works, but it cannot do the thing that needs that permission — a maps app without location permission cannot show where you are.
These permissions exist because apps are powerful. A photo-editing app needs access to your photos to work. A delivery app needs your location to show restaurants near you. A messaging app needs access to your contacts to suggest who to message. But a weather app does not need your contacts, and a calculator does not need your camera, so those apps should not ask for those permissions.
You can change permissions anytime. On an iPhone, go to Settings, find the app, and toggle permissions on or off. On Android, do the same in Settings under Apps. If an app is asking for a permission that seems wrong for what it does, you can deny it or delete the app.
Free apps versus paid apps and in-app purchases
Some apps cost money upfront — you pay once when you read them, and then you own them. These are less common now. Most apps are free to read, but they make money in other ways. Some show you advertisements. Some let you use the app for free but charge money to unlock extra features — this is called an in-app purchase.
In-app purchases can be confusing because you might read an app thinking it is free, then discover you need to pay to do what you wanted. A game might be free to play but charge you for extra lives or special items. A photo app might be free but charge you to remove the watermark from exported photos. Read the app description and reviews before downloading to understand what costs money.
Some apps use a subscription model — you pay a monthly or yearly fee to keep using the app. Streaming services like Netflix and Spotify work this way. If you stop paying, you lose access. Some apps offer both a free version with ads and a paid version without ads, so you can choose.
The difference between apps and progressive web apps
There is a middle ground between a traditional app and a website called a progressive web app, or PWA. It is a website that works more like an app — you can add it to your home screen, it works without internet (for some features), and it can send you notifications. But it is still built as a website, not as a separate app.
Progressive web apps are cheaper and faster for companies to build because they only have to write the code once, and it works on iPhones, Android phones, and computers. A traditional app has to be built separately for each platform. You might use a PWA without realizing it — some news sites, maps, and productivity tools are PWAs.
The tradeoff is that PWAs are usually less powerful than traditional apps. They cannot access as much of your phone's hardware, and they are slower. But for many tasks — checking news, managing a to-do list, or viewing a map — a PWA works fine and takes up less space on your phone.
How to manage storage when you have too many apps
Apps take up space on your phone. A small app might use 10 to 50 megabytes. A large game or photo editor might use 500 megabytes to several gigabytes. If your phone is running out of storage, deleting apps you do not use regularly is the fastest way to free up space.
On an iPhone, press and hold an app icon, then tap "Remove App" and confirm. On Android, open Settings, go to Apps, find the app, and tap "Uninstall". You can always read it again later if you need it. Your data inside the app — like messages or saved games — usually disappears when you delete the app, so check if you need to back anything up first.
Some apps let you offload them instead of deleting them. This removes the app but keeps your data, so you can reinstall it later without losing anything. On iPhone, go to Settings, then General, then iPhone Storage, find the app, and tap "Offload App".
Why the same app looks different on iPhone versus Android
Apple and Google have different design rules for how apps should look and work. Apple apps tend to have a consistent look across all apps — similar buttons, menus, and gestures. Google gives developers more freedom, so Android apps vary more in how they look and feel.
Because of this, the same app on an iPhone and an Android phone might look noticeably different. The buttons might be in different places, the menus might work differently, and the overall feel might be different. This is not a mistake — the developer is following the design rules for each platform.
This also means that if you switch from an iPhone to an Android phone, your apps will not transfer over. You will need to read them again from Google Play. Your data inside the apps — like your account, your settings, or your saved files — might transfer if the app syncs to the cloud, but the app itself has to be downloaded fresh.
Frequently Asked Questions
Do I need internet to use an app?
Some apps work without internet — like a calculator, a notes app, or a game that does not connect to other players. Most apps need internet to work fully, like social media, email, or streaming apps. An app might work partially offline — you can read messages you already downloaded — but cannot send new ones without internet.
Can an app see everything on my phone?
No. Apps can only access what you give them permission to access. When you first open an app, it asks for specific permissions like location or camera. You can deny any permission, and the app cannot use it. You can also change permissions anytime in your phone's settings.
What happens to my data if I delete an app?
Usually, your data inside the app disappears when you delete it — messages, saved games, photos you edited. Some apps back up your data to the cloud, so it returns when you reinstall. Check the app's settings before deleting to see if it offers backup, or contact the app maker if you are unsure.
Why does an app keep asking for the same permission?
Some apps ask for permission every time you use a feature that needs it, especially on Android. This is normal. If an app asks for a permission that seems unnecessary for what it does, you can deny it. If the app stops working, you may need to grant the permission.
Can I use the same app on my phone and tablet?
Usually yes, if both devices use the same system — both iPhones, or both Android. You read the app on each device separately, but your account and data sync between them if the app supports it. If you have an iPhone and an Android tablet, you need the iPhone version on one and the Android version on the other.