CodeIgniter is very well-suited to those beginning PHP web development, and who are tired of writing the same code over and over (like authentication mechanisms). It is a very good choice for those looking for a framework that will not try to "dictate" how their application is designed and which choices are made. Situations where highly modular code is required and where more advanced features like queuing and hooking are needed are situations where CodeIgniter is not a good choice. More modern frameworks like CakePHP and Laravel are much better-suited.
Yii is very well suited if you love to program with Object Oriented PHP. This framework uses OOP very well and if you know this pattern you'll love it. The same applies for its MVC architecture and if you come from formal software development education. Also if you are in a bussiness enviroment and need a stable framework. This is the tool for you. It uses very formal scheme but I would like more open and hackable framework, and for this Yii2 is not a good option. Also, if you like to have bleeding edge technologies I don't recommend this framework.
CodeIgniter is an MVC framework that allows us to organize our code in a manner that it is easier to maintain and update. If you are working in a team environment and building an application or website like our dashboard, then CodeIgniter is a great solution.
Faced some issue of session management, so that's why we used the Core Session library for that. It would be great if we could improve it a little bit.
Frameworks provide the option to setup all getters/setters, so having this option in it is a great idea.
I think is really easy to use, it's not perfect but many developers with great experience will know how to exploit this framework to create great apps!
It's has a really good support based on online documentation and official forums. But sometimes I wish there were a paid service where to report some urgent issues.
Codeigniter's syntax patterns are expressive and elegant. Unit testing support. Well documented. but as CodeIgniter tries to retain backward compatibility with PHP 4, here comes Laravel to the rescue. It has good features and it is updated. Wikipedia has mentioned, “according to a March 2015 developer’s survey on PHP frameworks popularity, Laravel was listed as the most popular PHP framework of 2015, followed by Symfony2, Nette, CodeIgniter, Yii2, and others.
CodeIgniter has been a very good alternative for developing API endpoint for our Android applications and we received very good output through CodeIgniter.
Because the source code is smaller but comes with MVC pattern, it has the functionality to develop an application faster with MVC strategy.
Initial learning was hard, it has very specific tools and requires a basic knowledge that takes time to learn. But after that it's really fast and easy to do apps.
When it changed to version 2, servers had to be be upgraded due to the new requirements. Also it required to learn many things that were not backwards compatible.
It saves time by help us to create great applications in less time but very powerfuls.
