How to Install an application that requires android 5.0+ on android 4.4.4 I have a phone running android 4.4 and the app requires android 5.0 or higher. I want to install this app on android 4.4. Do you have any way, help yourself. Thank you very much.
Sometimes an app has the ability to run on an old device, but there is also something in an app's apk file, indicating the oldest version that can install this app. For example, maybe an app CAN be run on android 4.4 but the author of the app set the minimum supported version to android 5.0.
So it is possible to change it. Afterwards the app might be able to run on old devices, while it may also crash.  

An android app downloaded from Google Play or somewhere else is an apk file, which is actually just a zip compressed package, containing multiple files, e.g. dalvik bytecode, pictures, text resources. To learn more about apk file's structure you can just google it. One of the files is AndroidManifest.xml, that was originally a xml file before the author "compile" and publish the app. You don't have to know what is xml but it was "human readable" before being published and become unreadable when the app finally reached you. The AndroidManifest.xml have a line looks like android:minSdkVersion="8" , sdk version 8 means Android version 2.3, sdk version 23 means Android 6.0, search for "android sdk versions" to get a full list. Now however, this line had already been converted to something unreadable. We need something else.  

One of those things is apktool, it can "decompile" an xml or even the whole app back to what we can read and edit, then "compile" it back to apk. There're plenty of blogs about how to use apktool so I won't run into details. Using apktool you can decompile the apk, change the minSdkVersion to a very small number or just 1, compile the app back, then install.  

Notice:
1. You have to "sign" the apk after compiling it back. Google for details.
2. You have to uninstall the previously installed version of the app before reinstall the modified one.
3. Do not publish a modified apk, it's illegal.
4. Don't expact too much from this method. The app may still crash.
5. Though I often do this but it's really complicated for non-programmers to do the modification so feel free to ask, and prepare to give up at any moment.