Mobile apps have become an essential extension of how people interact with products and services. Whether you’re booking a flight, paying for coffee, or managing your retirement portfolio, you’re likely doing it through a smartphone. That popularity brings significant security challenges, especially with estimates showing more than 255 billion mobile app downloads in 2023 alone. Each of those downloads represents a potential opportunity for attackers if security best practices are ignored.

Two-factor authentication (2FA) has become a cornerstone of online security. It provides an extra layer of protection by requiring users to verify their identity in two ways—typically, something they know (a password) and something they have (a code sent to their phone). But implementing 2FA effectively requires balancing security with user convenience. Here’s a look at when and why you should prompt for 2FA, with specific timing recommendations and examples, including how to implement checks using PHP.

In the past we posted PHP code to generate CAPTCHA, and here is a small fix to the code that will make it more secure.

In last article I explained what CAPTCHA is and why it is used (you can find that article here). Here I will provide PHP code that crates and uses CAPTCHA.

CAPTCHA stands for Completely Automated Public Turing test to tell Computers and Humans Apart. This is a challenge-response test used on web-forms to ensure that the form is filed in by a human being, or in other words it is a form of protection from bots (computers) filling out forms.