When you are preparing for a pilot licence such as via the article PILOT CET How to Choose the Best Pilot Training Study Material you'll want to decide whether digital (online apps PDFs) or paper (textbooks printed notes) study material is better for you.
Digital study material:
Pros: Very convenient - you can carry many books/apps on one device access updates and online mock tests easily. This fits well with the Digital & Online Study Resources section of the article.
Cons: But there are distractions (notifications email) and dependence on power/internet. Research shows digital media may reduce focus and retention compared to paper.
Also, typing or reading on screen may mean you absorb less deeply. Hand writing or physical reading often helps better understanding.
Paper study material:
Pros: Textbooks, printed modules can help you focus better are free from digital distractions and allow easy annotation or highlighting. Studies indicate learners better gauge what they understand when reading on paper.
Cons: But they are less portable heavier to carry and updating content may be slower. Also you miss some features like search hyperlinks or interactive quizzes.
There's no simple one size answer. If you're studying technical subjects like Navigation Meteorology or Air Regulations (as the article suggests) you'll benefit from a mixture:
Use paper for deep understanding: when you have a printed book like the recommended textbooks (e.g., the Oxford ATPL series) and you want to really absorb the concepts.
Use digital for convenience revision mock tests and quick access: when you are travelling or when you need interactive question banks or simulation apps. The article lists both: best recommended books (paper) and digital & online study resources.
Since you are working toward how to choose the best pilot training study material:
Choose a core set of high-quality paper textbooks & modules for your main study.
Supplement with digital resources mock tests question banks apps to reinforce and track progress.
Use digital when you're on the go paper when you're stationary and want to concentrate.
If you prefer writing by hand (many pilots do) then paper might give you better retention. If you are comfortable with screens and organised digital apps then digital is fine.
Watch out for distractions on screens and always back up digital files.