Apple announced on its annual 2017 WWDC that it will be dropping all the 32-bit applications and will provide no support for these apps in future. The news was quite shocking for the majority of iPhone application development companies in USA as they need to update all their 32-bit apps to 64-bit to refrain from falling into the 'obsolete pit' of unsupported apps.

1. Apple’s 32-Bit App
Obsolete: How Will it
Impact You?

2. Apple announced on its annual 2017 WWDC that it will be
dropping all the 32-bit applications and will provide no support
for these apps in future. The news was quite shocking for the
majority of ​iPhone application development companies in USA
as they need to update all their 32-bit apps to 64-bit to refrain
from falling into the 'obsolete pit' of unsupported apps.
Why Apple Won't Support 32-Bit Apps?
As the company has come up with a new range of 64-bit
devices and iOS 11, all the 32-bit applications will face
compatibility issues. Currently, many iOS apps are available in
the app store in both 32 & 64-bit format. However, as the new
devices and OS are focused on the 64-bit system for increased
speed and device performance, using 32-bit apps will mess with
overall performance.

3. A legacy 32-bit application requires 32-bit subsystem to be
loaded before it could run on a 64-bit system resulting in a
huge compromise in device performance, app launch time, and
memory consumption.
Which iOS Devices are 64-bit?
iPhones, ranging from 5s to 7s, along with iPad Air and Air 2 are
64-bit devices. Ipad mini 2 to 4, 6-gen iPod touch, and the all
new 12.9-inch iPad Prod are 64-bit devices as well.
What of Your iOS Apps?
The new iOS 10.3 version enables the users to check which
applications will be running on the 32-bit support. While the

4. most of the apps would be updated to their 64-bit counterpart
by ​iPhone app development services in USA​, some apps (such
as gaming and abandoned once) that offer no financial value to
the developers will phase out and will possibly be made
defunct.
Thus, as a user, you needn't worry. Just update your favorite
apps and enjoy an enhanced device and OS performance.
For developers, this might turn out to be tricky to decide which
apps are worth upgrading to 64-bit and which aren't.
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07/04/apples-32-bit-app-obsolete-how-will-it-impact-you/