Publishing applications
Android application publishing is a process that makes your Android applications available to users. Infect, publishing is the last phase of the Android application development process.
Once you developed and fully tested your Android Application, you can start selling or distributing free using Google Play (A famous Android marketplace). You can also release your applications by sending them directly to users or by letting users download them from your own website.
You can check a detailed publishing process at Android official website, but this tutorial will take you through simple steps to launch your application on Google Play. Here is a simplified check list which will help you in launching your Android application −
- Step-1: Regression Testing Before you publish your application, you need to make sure that its meeting the basic quality expectations for all Android apps, on all of the devices that you are targeting. So perform all the required testing on different devices including phone and tablets.
- Step-2: Application Rating When you will publish your application at Google Play, you will have to specify a content rating for your app, which informs Google Play users of its maturity level. Currently available ratings are (a) Everyone (b) Low maturity (c) Medium maturity (d) High maturity.
- Step-3: Targeted Regions Google Play lets you control what countries and territories where your application will be sold. Accordingly you must take care of setting up time zone, localization or any other specific requirement as per the targeted region.
- Step-4: Application Size Currently, the maximum size for an APK published on Google Play is 50 MB. If your app exceeds that size, or if you want to offer a secondary download, you can use APK Expansion Files, which Google Play will host for free on its server infrastructure and automatically handle the download to devices.
- Step-5: SDK and Screen Compatibility It is important to make sure that your app is designed to run properly on the Android platform versions and device screen sizes that you want to target.
- Step-6: Application Pricing Deciding whether you app will be free or paid is important because, on Google Play, free app's must remain free. If you want to sell your application then you will have to specify its price in different currencies.
- Step-7: Promotional Content It is a good marketing practice to supply a variety of high-quality graphic assets to showcase your app or brand. After you publish, these appear on your product details page, in store listings and search results, and elsewhere.
- Step-8: Build and Upload release-ready APK The release-ready APK is what you you will upload to the Developer Console and distribute to users. You can check complete detail on how to create a release-ready version of your app: Preparing for Release.
- Step-9: Finalize Application Detail Google Play gives you a variety of ways to promote your app and engage with users on your product details page, from colourful graphics, screen shots, and videos to localized descriptions, release details, and links to your other apps. So you can decorate your application page and provide as much as clear crisp detail you can provide.
Important: You will need to export your application as an APK (Android Package) file before you upload it Google Play marketplace.
To export an application, just open that application project in Android studio and select Build → Generate Signed APK from your Android studio and follow the simple steps to export your application −
1. Next select, Generate Signed APK option as shown in the above screen shot and then click it so that you get following screen where you will choose Create new key store to store your application.
2. Enter your key store path, key store password, key alias and key password to protect your application and click on Next button once again. It will display following screen to let you create an application −
3. Once you filled up all the information, like app destination, build type and flavors click finish button While creating an application it will show as below
4. Finally, it will generate your Android Application as APK format File which will be uploaded at Google Play marketplace.
Some of App markets
• Aptoide
• Fdroid
Signing applications
Android requires that all APKs be digitally signed with a certificate before they are installed on a device or updated. When releasing using Android App Bundles, you need to sign your app bundle with an upload key before uploading it to the Play Console, and Play App Signing takes care of the rest. For apps distributing using APKs on the Play Store (created before August 2021) or on other stores, you must manually sign your APKs for upload.
The following is a high-level overview of the steps you might need to take to sign and publish a new app to Google Play:
• Generate an upload key and keystore
• Sign your app with your upload key
• Configure Play App Signing
• Upload your app to Google Play
• Prepare & roll out release of your app
If instead your app is already published to the Google Play Store with an existing app signing key, or you would like to choose the app signing key for a new app instead of having Google generate it, follow these steps:
• Sign your app with your app’s signing key and select the option to encrypt and export its signing key.
• Upload your app’s signing key to Play App Signing.
• Generate and register an upload certificate for future updates to your app
• Upload your app to Google Play
• Prepare & roll out release of your app
Play App Signing
• With Play App Signing, Google manages and protects your app's signing key for you and uses it to sign your APKs for distribution. And, because app bundles defer building and signing APKs to the Google Play Store, you need to configure Play App Signing before you upload your app bundle. Doing so lets you benefit from the following:
• Use the Android App Bundle and support Google Play’s advanced delivery modes. The Android App Bundle makes your app much smaller, your releases simpler, and makes it possible to use feature modules and offer instant experiences.
• Increase the security of your signing key, and make it possible to use a separate upload key to sign the app bundle you upload to Google Play.
• One time key upgrade for new installs lets you change your app signing key in case your existing one is compromised or if you need to migrate to a cryptographically stronger key
• Play App Signing uses two keys: the app signing key and the upload key, which are described in further detail in the section about Keys and keystores. You keep the upload key and use it to sign your app for upload to the Google Play Store. Google uses the upload certificate to verify your identity, and signs your APK(s) with your app signing key for distribution as shown in figure 1. By using a separate upload key you can request an upload key reset if your key is ever lost or compromised.
• By comparison, for apps created before August 2021 that have not opted in to Play App Signing, if you lose your app’s signing key, you lose the ability to update your app.
Important: Your keys are stored on the same infrastructure that Google uses to store its own keys, where they are protected by Google’s Key Management Service
Definitions: Keystores, keys, and certificates
• Java Keystores (.jks or .keystore) are binary files that serve as repositories of certificates and private keys.
• A public key certificate (.der or .pem files), also known as a digital certificate or an identity certificate, contains the public key of a public/private key pair, as well as some other metadata identifying the owner (for example, name and location) who holds the corresponding private key.
• The following are the different types of keys you should understand:
App signing key: The key that is used to sign APKs that are installed on a user's device. As part of Android’s secure update model, the signing key never changes during the lifetime of your app. The app signing key is private and must be kept secret. You can, however, share the certificate that is generated using your app signing key.
Upload key: The key you use to sign the app bundle or APK before you upload it for app signing with Google Play. You must keep the upload key secret. However, you can share the certificate that is generated using your upload key. You may generate an upload key in one of the following ways:
If you choose for Google to generate the app signing key for you when you opt in, then the key you use to sign your app for release is designated as your upload key.
If you provide the app signing key to Google when opting in your new or existing app, then you have the option to generate a new upload key during or after opting in for increased security.
If you do not generate a new upload key, you continue to use your app signing key as your upload key to sign each release.
Learn More:
1. https://developer.android.com/studio/publish/app-signing
2. https://stuff.mit.edu/afs/sipb/project/android/docs/tools/publishing/app-signing.html