Authentication Apps: How They Work and 5 Apps to Know About

An authentication app is a software application that is used to authenticate the identity of a user. Authentication is the process of verifying that someone is who they claim to be, typically by requiring the user to provide a username and password. An authentication app can also use other forms of authentication, such as fingerprints, facial recognition, or security tokens.

Authentication apps can be used for a variety of purposes, such as logging into a website or mobile application, accessing a secure network, or making a financial transaction. They can also be used to provide multi-factor authentication, which adds an additional layer of security by requiring the user to provide multiple forms of authentication, such as a password and a fingerprint.

In this article:

How Do Authenticator Apps Work?

Most authenticator apps work by using a technology called Time-based One-Time Passwords (TOTP). TOTP is an algorithm that generates a unique code at regular intervals (for example, every 30 seconds). The code is based on the current time and a shared secret key that is shared between the authenticator app and the service or website that the user is trying to access. 

The process typically works like this:

  1. When users set up an authenticator app, they scan a QR code or manually enter a secret key provided by the service they are trying to access. This key is then stored in the authenticator app. 
  2. When the user wants to log in, the authenticator generates a code based on the current time and the secret key. 
  3. Users enter this code along with their username and password. 
  4. The service or website uses the same algorithm to generate a code based on the current time and the secret key, and compares it to the code entered by the user. If the codes match, the user is granted access.

Because the code is generated based on the current time and a shared secret key, it is unique and can only be used once, making it more secure than traditional static passwords.

Top 5 Authentication Apps to Consider in 2023

Google Authenticator

Pricing: Free

Website: Find it on Google Play or the Apple Store

Google Authenticator is a mobile app that generates two-factor authentication (2FA) codes on a user’s smartphone. It can be used to provide an additional layer of security for online accounts, such as Google, Facebook, and many others by requiring a code in addition to a password in order to log in. 

This code is generated by the app on the user’s device and is valid for a short period of time, providing an extra level of security by ensuring that only the user with physical access to the device can log in.

Microsoft Authenticator

Pricing: Free


This mobile authenticator allows users to authenticate their identity using 2FA or multi-factor authentication (MFA). It uses a phone or tablet as a second form of identification in addition to a password, helping to protect against unauthorized access to a user’s accounts. 

The app can be used to generate TOTP and push notifications for account sign-ins, and also supports the use of a fingerprint or face recognition as an alternative to entering a password. It’s available for both iOS and Android.

LastPass Authenticator

Pricing: Free


LastPass is a password manager that allows users to securely store and manage their login credentials, as well as other sensitive information, in a central location. It uses encryption to protect the data, and allows users to easily access their information on multiple devices through a browser extension or mobile app. 

LastPass Authenticator is a mobile app that provides an additional layer of security for LastPass users. It uses 2FA to verify the user’s identity before allowing access to the password manager. When logging in to LastPass, in addition to entering a master password, the user will also need to provide a code generated by the Authenticator app. 


Pricing: Free


Authy is a mobile application and service that provides 2FA for online accounts. It uses a combination of a phone number and a one-time code generated by the app to confirm a user’s identity and add an extra layer of security to login attempts. Authy also supports the use of a hardware token for 2FA.

2FA Authenticator

Pricing: Free


2FA is an authenticator app that allows adding online accounts manually or using a QR code. Unlike Google Authenticator, 2FA Authenticator creates cloud backups of registered accounts in iCloud or Google Drive (depending on the device’s operating system), ensuring users retain access even if they lose their phone or get a new one. This backup is encrypted and accessible only from the 2FA Authenticator app.

How to Choose an Authentication App

When choosing an authentication app, it’s important to consider the following factors:

  • Security: The app should use strong encryption and other security measures to protect the user’s data and prevent unauthorized access. Look for apps that are compliant with leading industry standards such as FIDO.
  • Ease of use: The app should be easy to set up and use, with a user-friendly interface. It should also be compatible with different types of devices and operating systems, such as iOS and Android.
  • Multi-platform support: The app should be able to work across different platforms, such as web, mobile, and desktop, and should be able to integrate with other tools and services.
  • Backup and recovery: The app should have options for backup and recovery in case the user loses access to their device or the app.
  • Support: The app should have a dedicated support team that can help you troubleshoot any issues and answer any questions you may have.
  • Scalability: The app should be able to handle a large number of users and transactions, and should be able to scale as your organization grows.
  • Compliance: The app should comply with any relevant regulations and standards, such as PCI-DSS, HIPAA, and SOC2.

By considering these factors, you can choose an authentication app that provides the security, ease of use, and scalability that your organization needs. It’s also important to test the app before making a final decision and make sure it meets your organization’s needs.

Authentication for SaaS with Frontegg

Frontegg’s solution provides a flexible authentication-as-a-service solution for all kinds of B2B use cases. Starting from powerful user-based authentication flows, based on commonly-used authentication protocols such as OAuth, Open ID connect, SAML, and WebAuthN, all the way to granular role and permission management via a centralized dashboard. There’s also provision for MFA, User lockouts, Device verification and more. 

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