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However, Apple deprecated bitcode in Xcode 14 and removed support,
so it has been removed from the Flutter 3.7 release.Of course, we recommend that you measure your own app.
To do that, see Measuring your app’s size.<topic_end>
<topic_start>
How does Flutter define a pixel?
Flutter uses logical pixels,
and often refers to them merely as “pixels”.
Flutter’s devicePixelRatio expresses the ratio
between physical pixels and logical CSS pixels.<topic_end>
<topic_start>
Capabilities
<topic_end>
<topic_start>
What kind of app performance can I expect?
You can expect excellent performance. Flutter is
designed to help developers easily achieve a constant 60fps.
Flutter apps run using natively compiled code—no
interpreters are involved.
This means that Flutter apps start quickly.<topic_end>
<topic_start>
What kind of developer cycles can I expect? How long between edit and refresh?
Flutter implements a hot reload developer cycle. You can expect
sub-second reload times, on a device or an emulator/simulator.Flutter’s hot reload is stateful so the app state
is retained after a reload. This means you can quickly iterate
on a screen deeply nested in your app, without starting
from the home screen after every reload.<topic_end>
<topic_start>
How is hot reload different from hot restart?
Hot reload works by injecting updated source code files
into the running Dart VM (Virtual Machine). This doesn’t
only add new classes, but also adds methods and fields
to existing classes, and changes existing functions.
Hot restart resets the state to the app’s initial state.For more information, see Hot reload.<topic_end>
<topic_start>
Where can I deploy my Flutter app?
You can compile and deploy your Flutter app to iOS, Android,
web, and desktop.<topic_end>
<topic_start>
What devices and OS versions does Flutter run on?
We support and test running Flutter on a variety
of low-end to high-end platforms. For a detailed list
of the platforms on which we test, see
the list of supported platforms.Flutter supports building ahead-of-time (AOT) compiled libraries
for x86_64, armeabi-v7a, and arm64-v8a.Apps built for ARMv7 or ARM64 run fine (using ARM emulation)
on many x86 Android devices.We support developing Flutter apps on a range of platforms.
See the system requirements listed under each
development operating system.<topic_end>
<topic_start>
Does Flutter run on the web?
Yes, web support is available in the stable channel.
For more details, check out the web instructions.<topic_end>
<topic_start>
Can I use Flutter to build desktop apps?
Yes, desktop support is in stable for Windows,
macOS, and Linux.<topic_end>
<topic_start>
Can I use Flutter inside of my existing native app?
Yes, learn more in the add-to-app section of our website.<topic_end>
<topic_start>
Can I access platform services and APIs like sensors and local storage?
Yes. Flutter gives developers out-of-the-box access to some
platform-specific services and APIs from the operating system.
However, we want to avoid the “lowest common denominator” problem
with most cross-platform APIs, so we don’t intend to build
cross-platform APIs for all native services and APIs.A number of platform services and APIs have
ready-made packages available on pub.dev.
Using an existing package is easy.Finally, we encourage developers to use Flutter’s
asynchronous message passing system to create your
own integrations with platform and third-party APIs.
Developers can expose as much or as little of the
platform APIs as they need, and build layers of
abstractions that are a best fit for their project.<topic_end>
<topic_start>
Can I extend and customize the bundled widgets?
Absolutely. Flutter’s widget system was designed
to be easily customizable.Rather than having each widget provide a large number of parameters,
Flutter embraces composition. Widgets are built out of smaller
widgets that you can reuse and combine in novel ways to make
custom widgets. For example, rather than subclassing a generic
button widget, ElevatedButton combines a Material widget with a
GestureDetector widget. The Material widget provides the visual
design and the GestureDetector widget provides the
interaction design.To create a button with a custom visual design, you can combine
widgets that implement your visual design with a GestureDetector,
which provides the interaction design. For example,
CupertinoButton follows this approach and combines a
GestureDetector with several other widgets that implement its
visual design.Composition gives you maximum control over the visual and
interaction design of your widgets while also allowing a
large amount of code reuse. In the framework, we’ve decomposed
complex widgets to pieces that separately implement
the visual, interaction, and motion design. You can remix
these widgets however you like to make your own custom
widgets that have full range of expression.<topic_end>
<topic_start>
Why would I want to share layout code across iOS and Android?
You can choose to implement different app layouts for
iOS and Android. Developers are free to check the mobile OS
at runtime and render different layouts,
though we find this practice to be rare.More and more, we see mobile app layouts and designs evolving