I'd at the least throw away apps and learning games, in favour of books (especially those with audio samples available).
Duolingo isn't optimized for Japanese and it shows some major pain points especially around kanji and Japanese grammar.
There are a lot of more specialized Japanese learning apps if you need an app, and also many good textbooks and video lessons that are probably better than most apps.
Stay away from Duo. There's no structure to its teaching of Japanese, and it's not set up to let you intuit the grammar or structure either.
There are several ways of learning Kanji, each with their benefits and drawbacks, such as WaniKani, Remembering the Kanji, Kodansha Kanji Learner's Course, etc. Ultimately, Kanji are painful and time-intensive to learn, so none of these will be perfect, but you can maybe spend some initial time trying to find out which works best for you and then just stick with it.
Well you see the exact issue with Duolinguo as pointed by others is that you feel you progressed for some months while in reality you didn't. If by the "characters" you mean hiragana and katakana both set can be learn to basic proficiency in a week (actually over a weekend for motivated people). If you mean kanji, the first set of 80 can be done quietly in a month (3 weeks in my case, when I was in high school, no tutor, no class, wikipedia only).
Duolingo can help you with the absolute start, dipping the toes. But it won't teach you a language on even a basic level. It can work as a tool to exercise basic vocabulary, but that's not a language.
I've had success with learning a language passively just by reading books (there are easier ones for learners) and watching TV shows (with subtitles) / listening to podcasts. It takes time and can be sometimes frustrating, but can be down on your own.
Learning to speak and write is a different matter, and basically you need a tutor for that and a lot of practice.
Frankly, there are 3 things that I find annoying / frustrating:
- Pronunciation: Sometimes the recorded audio is in so bad quality or spoken in robotic way, that is very hard to repeat it.
- Gamification: After reaching 1st place in the Diamond League, I found the constant nagging about my ranking annoying. However, some users I follow have found it fun and have been in the Diamond League for over 70 weeks. I have also noticed that some players like to compete with others, it sometimes leads to visible competition for the top 3 places (especially in the Obsidian League), which is really fun.
- Catchy answers: It is not a problem to spend a whole day with Duolingo, but after 15 minutes you need to take a short break. Otherwise you lose your focus and may find that the answer you have entered is not one that Duolingo would accept. This is because many answers look good enough, but in reality the other one is correct. Personally, I have had to click on the icon several times to open a forum to find an explanation of the error.
Disclaimer: I am paying Duolingo user with 340+ day streak trying to learn French. I have never had a French classes, but recently I had no problem to chat with other real person in French.
Even worse, sometimes it's just plain wrong. I tried Duolingo for a few months at the end of 2021 to augment my Japanese lessons. At some point, there was a content update introducing a few additional voices. But the new voices were so buggy that they would sometimes read certain characters in a completely wrong way, i.e. they were using kun'yomi readings where it should be on'yomi and the other way around. (I don't remember the concrete example, but imagine something like 先に being read as "sen'ni" instead of "sakini". That's a mistake that a native speaker would never ever make.)
^This. Spot on. I was fooled by Duolingo and wasted way too much time on it before I caught on and deleted everything Duolingo from all my devices. Now I'm finally making actual progress in my language learning. I never used Duolingo alone, of course, but the effort I spent there impacted my learning negatively and made everything ineffective.
Stay away from Duolingo. It's fool's gold.
And for myself too. I did had improvements I never got with self learning before. For me the gamification is the big thing that actually helps to keep on doing. One large reason for why I would not be to improve in language without duolingo is that makes the boring parts actually fun and keeps you engage to keep going. It wont make you fluent on itself, but it makes learning language feel less like horrible chore.
In reality, going from duolingo to reading anything more complex than a childrens book and holding a conversation more complex than ordering a coffee is only marginally easier than just trying to learn that directly.
It allows you to postpone the difficult parts of learning a language indefinitely while making it feel like steady progress. And our brains absolutely love that.