Are Xamarin iOS apps bloated unreasonably?

问题:

I'm developing a reasonably simple app using Xamarin iOS and the smallest size I've gotten for the .app file is 13.5 MB.

I've performed all the recommended optimizations - no debug symbols, LVVM code generation, thumb-2, link all assemblies, single architecture only (ARMV7).

The first question is, does my 13.5 MB sound like something to be expected from Xamarin iOS, or am I likely doing something wrong?

The second question is, how much extra size overhead does Xamarin iOS add to an equivalent native implementation (roughly)?

The third question is, roughly how small can a Hello World app get compiled down to using Xamarin iOS?

The fourth question is, roughly how small can a native Hello World app get compiled down to?

回答1:

The .dSYM is a directory that includes debugging symbols. This is not something you're shipping as part of your application (to your end users). Note that this is produced even in non-debugging builds since it allows you to symbolicate crash reports (that comes from end users running the release binary).

For the real application size you need to look at the .app directory.

You can learn quite a few tricks to reduce your application size (and build time) by watching this year Evolve video Advanced iOS Build mechanics. That will also answer the other questions you had.

回答2:

Xamarin apps are a bit larger in release mode, as one would expect. As an example, looking at my binaries from two shipping apps, the binary + dlls are around 12m and 18m (I think I need to look into why the 18m one is so much bigger...). I would guess if I had done these in objective-c they would have been around half that size, from past experience building native apps.

If you're running debug hardware builds, they are enormous. the 12m example above jumps up to 96M (?!) for binary + dlls. Before I checked this, I had in my head that they doubled in size to deal with software debugger, but I guess there's a whole lot of other crap going in that I wasn't aware of.