Ux is a fairly new field and many methods are only getting perfected recently, while many methods are just hatching.

What shall we use, Agile or Lean UX? To answer such question we first have to get to know both methods.
Agile UX
The Agile UX has it’s roots in Agile, a framework for software development that puts great focus on team collaboration, and efficiency. But user experience design is not part of Agile, this and the fact that user centric design and development is key in today’s software world, a change had to be made. Agile UX embraces the principles of Agile and rethinks them in the context of UX.Great for tracking progress and keeping it in check, ensuring constant workflow and quality. Agile has no designated place for user experience design, you have to make it. Enables great collaboration between developers and designers.
Pros:
Tracking progress
Constant workflow and quality
Great collaboration potential between developers and designers
Cons:Not designed with UX in mind
Lean UX
is a more design-centric framework to software development, one in which the goal is to push a minimum viable product (MVP) onto the market as soon as possible. It cuts off ‘bulk’ from the workflow such as extensive documentation.
Early customer validationover releasing products with unknown end-user value.
Collaborative designover designing on an island.
Solving user problemsover designing the next “cool” feature.
Measuring KPIsover undefined success metrics.
Applying appropriate toolsover following a rigid plan.
Nimble designover heavy wireframes, comps or specs.
Which one to go for? Lean UX or Agile?There is no simple answer to this question as you might have guessed. If you can afford a somewhat longer deadline and with more detailed workflow to release a polished full version, I suggest Agile UX. If your game is speed, MVP and getting rid of ‘extra steps’ jump into Lean UX.
We at Pocket Solutions use both methods from time to time, but recently we resorted to using Lean more often. One thing is certain your team has to practice both to be efficient.