I had a similar situation.I was able to install app in debug mode using USB but not a signed version. I was able to install signed version on other phone, but not on my device. Numerous reasons and solutions did not help me. But one direction I got from a solution "uninstall for all users". What I did is to again install app in debug mode using USB connection, go to app details and "uninstall for all users" from right top 3 dots - to remove debug version. This looks like cleared all kinds of references. I usually do a normal uninstall.

现在我能够在设备上获得签名APK并成功安装。

如果你尝试了上面所有的答案，没有一个有效，你可能想试试这个:

如果你的构建变量是“调试”，那么你应该在应用程序构建gradle的buildTypes下添加这个，以便应用程序安装到你的设备上:

debug {
    minifyEnabled false
}

当我将android从2.3.2升级到3.0.1时，我就遇到了这个问题。如果是这种情况，IDE将自动考虑以下几点。

1.你不能通过传统的方法安装android:testOnly="true"的应用程序，例如从android文件管理器或从网站下载

2.Android Studio在运行的apk上设置Android:testOnly="true

如果您运行应用程序时直接将设备连接到系统，apk将安装和运行没有问题。

如果你从构建、放置和调试文件夹中复制这个apk，它将永远不会安装到设备中。

解决方案:Build -> Build APK(s) ->复制APK文件共享到您的团队

这样你的问题就解决了。

如果您正在使用cordova，请尝试卸载任何以前通过cordova构建的应用程序。 很奇怪，但是这个方法解决了我的问题

打开AndroidMainfest，然后在应用程序标签中添加verionCode, versionName，并确保debug able等于false:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="...">

<application
    ...
    android:debuggable="false"
    android:versionCode="1"
    android:versionName="1.0"
    tools:ignore="HardcodedDebugMode">
    ...
</application>

然后打开构建。gradle (module:app)确保verionCode, versionName退出和minsdk <=您的移动sdk:

defaultConfig {
    ...
    minSdkVersion 19
    targetSdkVersion 28
    versionCode 1
    versionName "1.0"
   ...
}

查阅资料来源:https://developer.android.com/studio/publish/

https://developer.android.com/studio/publish/preparing &

https://developer.android.com/studio/publish/versioning &

和https://developer.android.com/studio/publish/app-signing

确保考虑到以下建议:

Your build variants and Flavors should be same(App installed and new one), usually release Signature file must be the same(*.jks file) The version you set in build.gradle or AndroidManifest have greater value compared to current version(it is recommended to set version in build.gradle) URL is correct(doesn't have typo) and server is reachable(WebService/WebMethod/WIFI is running/available and ...) File downloaded completely File saved correctly into desired directory Setting for Data and Type in setDataAndType is correct