Intrusive ads and aggressive premium prompts

"Third party ads make this app absolutely miserable. Your own ads for premium were bearable, but ads for random games ruin the experience." and "It kept asking for me to get the free trial but I kept ignoring it; then I got 5 ads in one day prompting the free trial."

Energy system forces paid subscription

"The energy system makes it effectively no longer a free app, punishing you for daring to learn." and "You can’t even get through a single lesson without an ad popping up to buy their plan. You also run out of energy super fast."

Timed lessons feel stressful

"It’s annoying to be timed!!"

Content sometimes feels irrelevant or off‑topic

"The transgender stuff on the story is really disgusting and I wish I could remove it." and "Learning to ask for a lawyer wasn’t as handy; I felt I wasted a year using Duolingo."

App icon redesign is unappealing

"The current icon (the owl with a bandage) looks damaged and less inspiring than the original."

XP reward reduction bug after lessons

"There’s a bug that sometimes cuts down the XP you’re supposed to get with a triple XP boost, reducing 120 XP to 40 XP."

Spelling validation bug in Polish lesson

"After the free trial, the word 'apple' in Polish wouldn’t accept the correct spelling, locking me in the lesson."

Occasional glitches interrupting learning flow

"Duolingo just always glitches out, making it hard to continue lessons."

Effective gamification keeps users engaged

"The gamification (leagues and streaks) is addictive in a good way; it makes learning feel like a game rather than a chore."

Generous free version compared to competitors

"Free version is very generous compared to other apps, allowing me to learn without paying."

Stories feature improves reading comprehension

"The ‘Stories’ feature is great for reading comprehension and keeps me interested."

Chess lessons are a popular and effective addition

"The chess lessons are awesome! After one month I zoomed up the rankings."

Streak reminders help maintain daily practice

"Duolingo sends reminders for your streak; it’s helped me keep a consistent learning habit."