For most app product managers, app performance is the highest priority, but they have no idea why performance is so important, let alone how to understand these performance metrics. This article introduces the what, why and how of the three questions about the magic number of APP performance.
Performance means different things to different people. Let's discuss speed. How long does it take to fully load and display the application from the start? How long does it take from clicking the menu to displaying the menu content? How long does it take from posting to appearing in the feed? This is important. If the server is slow to respond, or if a large number of images take time to load, users won't understand this. Users don't care if the app has to check the network for the latest news before it can be shown to them. Users expect applications to be responsive and they care about what they see.
What the user doesn't see doesn't matter
Apps are designed for people. Every moment a user waits for a response from an app, they consider quitting the app, or just leaving somewhere else. The good news for the app team is that if the delay is small enough, the human will not notice the delay. Few people will notice a delay of less than 100ms. Many of the best apps can complete more than 90% of their operations within 30 milliseconds.
Less than 100ms of latency is noticeable to very few people
Where do most people notice the "lag", 300ms. About 80% of people will notice a delay of more than 1/3 of a second. If your app takes 200ms or less in some areas, you may not expect much benefit from performance optimizations in those areas. If in some ways your app takes longer than 300ms to load, your users will notice. Although there is no official data, the longer the APP takes to load, the higher the possibility of users abandoning the APP, which may bring negative reviews and even switch to other competing products.
According to a study by Twinprime, a popular coffee app, more than half of its users abandoned mobile transactions last year. 37% of abandoned transactions are due to app performance issues, i.e. a year of app performance issues that could waste $9 billion in potential transactions.
Performance affects your bottom line. Statistics for mobile apps are sparse, but we can get some ideas by surveying the performance of web pages. If we had good cell phone statistics, we would find that cell phone users have less patience than PC users (data from Kissmetrics)
40% of people give up when a website takes more than 3 seconds to load
Every 1 second delay in page response time can result in a 7% lower conversion rate
Where is the performance problem? Beyond the app itself, there are many sources of performance issues, from slow content servers to mobile networks, often more than you might think. If an action in your app requires a network connection, it's a good idea to preload data in the background before the user requests it so they won't be affected by the network. Here is a typical practical example.
The network takes close to 1 second, which users will obviously notice. The lesson here is not to have to request the network in real time. Most apps make unnecessary real-time network requests without preloading. If your app needs to make network requests, please make sure that the server is fast, you only request once, the requested content will be cached, and the UI will be updated in very little time to load data. Likewise, if your app starts slowly, users will abandon your app. We've been talking about operational performance in programs, but what about startup time? Users have more patience and understanding about app startup times, but if it's slow, they'll abandon your app. About 60% of users expect apps to launch in less than 2 seconds. If your app takes longer to load, users will abandon your app even if it has a nice splash screen to try and hide the delay.
So, what are the magic numbers for app performance to watch out for? 100ms, 300ms, 1s and 2s:
Original: https://www.linkedin.com/pulse/magic-numbers-app-performance-jason-arbon