App Performance and Instruments Virtuoso

A full-length in-depth online course
on app performance and Instruments

“James Dempsey’s Instruments Virtuoso course is the best way I know to learn Apple's Instruments application.

Although Instruments has an intimidating interface at first look, James broke the app down into understandable pieces.

Previously I tried self-exploration, WWDC videos, and docs, but none of those options satisfied my curiosity.

This course focused on a mental model for understanding how an app operates under the hood, and how Instruments should be a key part of mobile app development from "New Project..." to after the app is in the hands of users.”

- @bobdel

“I really enjoyed that we had the time to dig in to corners of Instruments and problem solving in general.

You managed to create an environment where people weren't afraid of asking questions.

This course will open pandoras box of getting to know the inner workings of your application and the system on which it runs to find and fix performance issues.

Expand your day to day toolset and see how to apply Instruments.”

- @barkoded

“The course is great. I already have used this knowledge to speed up a couple of my frameworks. This is awesome!

Just do it. Investigating performance problems is quite a hard task, and if you don’t have a tool to do it, you’re very limited. Your apps will literally be worse without this knowledge.”

- Alex B.

“The course was well thought out and carefully delivered. I appreciated how well you handled the various levels of familiarity with the subject matter and tool.

The various insights that you and other classmates shared are now things to keep in mind while coding.”

- TJ U.

“Thank you for this amazing workshop!

I learned about things that I didn’t know even existed. I’ve already learned the knowledge to catch a few sneaky bugs in my job.

There is no better way to learn about Xcode’s Instruments!”

- R. M.

“Thank you again for an amazing course. I enjoyed this course thoroughly.

I’m newer to Apple development and have been mostly self taught. I had tried to use Instruments before on my own to problem solve some memory related performance issues. But I never really got anywhere.

It’s really great that now I can open Instruments and have my bearings. Familiarity with the Time Profiler alone is a skill that will serve me well!”

- John G.

“I really enjoyed James's laid back but thorough presentation style. The material was presented at just the right pace, not too fast, but not too slow.

By the end I felt that the material was well covered and I was not left with unanswered questions.”

- Jim R.

“Thanks for the lovely course!

I think it’s likely already paid for itself in terms of enhanced productivity and software.”

- Tom B.

“The course was well-structured, a complex topic was explained in a simple way, making it easier to build a strong foundation.

This has given me a great starting point for using Instruments to troubleshoot issues effectively.”

- Ravi S.

“This course has helped me dive into Instruments.

Before when I tried to investigate problems I had more questions about what Instrument's data means. Now I have information for understanding.”

- Kostaintyn K.

“No matter what your skill level, you will learn something that will make you a better developer.”

- Philippe C.

“The practical, hands-on sessions provided immediately useful techniques for performance analysis.

What really stood out was how effectively James builds a strong mental model, making complex Instruments concepts accessible and empowering you to tackle deep, real-world performance challenges.”

- Ken W.

“Amazing! The course was pretty easy to follow and understand.

I now know more about Instruments, how it works, but also how to use it in my own application.”

- Mikaela C.

“This course offers a practical and efficient approach to mastering app performance and Instruments.

It’s ideal for developers at any experience level.”

- Ilker U.

“The course is 100% worth the price. It might seem expensive but you’ll gain invaluable knowledge not easily available anywhere else.

I’ve already started applying the skills I learned from the course in my job and made quite a few performance improvements.”

- Bogdan B.

“I have tentatively used the Instruments app many times in the past, but never felt like I knew what I was doing.

This course built a scaffold to connect fundamental CS concepts to using Instruments to solve real problems.”

- Brian Y.

“OMG SO GOOD.

James has that rare skill of taking something incredibly complex, breaking it down, and explaining the component parts AND how they all inter-relate.”

- Mark B.