I work at Stream and I'm immensely proud of what our team is working on here at the company. Most recently, we announced our Android SDK accompanied by an extensive tutorial for Java and Kotlin. The tutorial covers just about everything you need to know when it comes to using our Android SDK for Stream Chat. The Android SDK touches many features offered by Stream Chat – more specifically, typing status, read state, file uploads, threads, reactions, editing messages, and commands. Head over to https://getstream.io/tutorials/android-chat/ and give it a whirl!

Can anyone help me decide what's best for app development or even android Oreo development? I'm in a state dilemma at the moment. I want to do Android programming, not necessarily web development. I have heard a lot of people recommend one of these, and it seems that both the tools can do the job. Which language would you choose?

Hi, Well...It depends. Take this with a grain of salt as I'm not a mobile app developer. I would weigh in some factors. If I would want to go fast, maybe I would make an Android app and use the language that I know, Java or even Kotlin. It really depends on how much time do you have. Alternatives to Flutter you can find here: https://buildfire.com/programming-languages-for-mobile-app-development/. As you already went with Firebase it might be a good option to stick with Flutter as they are both Google products and their integration might work more smoothly.
I would also take into account the job market in your area and your personal preference in order to raise your chances to find a good job after you graduate and use your project as actual work experience. I guess it would help to put in some specs related to what you are trying to build, as some frameworks are better suited to do one job, rather than others and hopefully get more specific answers.