Imagine you have an upcoming interview at Big Tech.
You see 2 coding rounds, 1 behavioural round, and …. 1 System Design.
This was originally published on https://www.mockingly.ai/blog
You start to wonder if it’s backend system design, or will it be focused on Android or iOS if you’re an iOS engineer (since I’m an Android Engineer, I’ll use Android more often in this post but all the tips apply to iOS devs too).
Most of us mobile devs have gone through this dilemma, and it’s not invalid. I’ve had interviews for an Android engineer role, where I was asked backend system design questions.
Because the interviewer was not an Android dev. For them, and for the general audience, system design equals backend system design.
But Android system design rounds are becoming more popular and are a focus point in big tech.
More so if you’re a Senior since that’s a level decider for your role. Your total comp depends on how well you do in your System Design and Behavioural rounds.
If you’re a junior, then prepping for system design rounds will help you cement your place. With the bar set so high nowadays, it never hurts to have all bases covered.
No BS Preparation for Android System Design
It doesn’t have to be complicated. And the good news is, there are fewer moving parts in Android System Design than backend. Here’s a simple step-by-step preparation strategy for your next Android system design interview:
Prepare a list of questions: Research online, or get Mockingly Pro to get a list of previously asked system design questions for Android.
Solve one question and analyse: We need to understand the baseline. What are your strengths and weaknesses, and are you able to think in blocks?
Once you’ve identified areas where you go blank: Next up, you should check out a solution for that same problem. Look online and I’m sure you’ll find some good solution. Or try weebox on GitHub.
Solve the question again, now that you have had a look at the solution. It’s important to solve the same question again, to internalise whatever you learnt.
Do this for three to four questions, and you’ll already start feeling confident.
Next up, let’s prepare for trivia.
The interviewer, more often than not, will grill you on your decisions, for example:
Why did you choose SQL over a No-SQL db?
Did you consider Shared Preferences? Why/why not?
Web Socket vs REST vs GQL, which one would you choose and why?
What’s REST? And how does it work?
Difference between HTTP and HTTPS (very common question).
Some Android/iOS specific trivia like lifecycle management, memory leaks, perf optimisations.
Having this trivia at the back of your head will help you when the interviewer tries to grill you on your decisions. Once you’re done with these, it’s time to put what you’ve learnt to the test.
Mock interviews are the key:
There’s little substitute for mocks as they resemble the real interview most closely.
Press enter or click to view image in full sizeMockingly.AI’s interface has a whiteboard to draw and get it reviewed by AI
Use mockingly.ai to prepare for system design. Especially Android system design as it has mobile-focused questions and some of them are questions asked in real interviews.
Other mock providers are way too expensive for what they are. I feel mockingly is a good substitute at a fair price. Even though it sometimes can ask repetitive questions, if you steer the interview in the right direction, then it’s good enough to practice mocks.
Last minute:
Use the “real interview questions” section on mockingly, Weebox to read about system design questions and their solutions. You’ll be in luck if you get one of those already asked questions.
If you follow these steps thoroughly, I feel 1–2 months should be enough to put you in a good spot for your Android system design interview. This is based on my experience prepping for big tech interviews. Feel free to share your thoughts in the comments.
Resources used:
WeeBox
proAndroidDev on Medium
Mockingly Pro
Trivia on various websites
Good luck on your android system design journey. I hope this post will be of some help to anyone looking to prepare.