Download and update an APK in Titanium

request.js

module.exports = function request({ body, url, headers = {}, method = 'GET', timeout = 5000, json = false, file }) {
	return new Promise((resolve, reject) => {
		var client = Ti.Network.createHTTPClient({
			onload: function () {
				if (json) {
					return resolve(JSON.parse(this.responseText));
				}
				return resolve(this.responseText);
			},
			onerror: function () {
				const response = {
					status: this.status
				};

				if (json) {
					try {
						response.response = JSON.parse(this.responseText);
					} catch (e) {
						response.response = this.responseText;

					}
				} else {
					response.response = JSON.parse(this.responseText);

				}
				return reject(response);
			},
			timeout
		});

		// Prepare the connection.
		client.open(method, url);
		for (const [ headerName, value ] of Object.entries(headers)) {
			client.setRequestHeader(headerName, value);
		}

		if (file) {
			client.file = file;
		}

		// Send the request.
		if (body) {
			client.send(body);
		} else {
			client.send();
		}
	});
};

Tiapp Permissions.md

Add the below to your tiapp

<android xmlns:android="http://schemas.android.com/apk/res/android">
    <manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1">
      <uses-permission android:name="android.permission.REQUEST_INSTALL_PACKAGES"/>
      <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
      <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    </manifest>
  </android>

update.js

const request = require('/request');

const apk = Ti.Filesystem.getFile(Ti.Filesystem.applicationDataDirectory, 'kairos.apk');
// You don't need to use this custom request wrapper, just a normal createHTTPClient call would do
await request({
	url: versionInfo.installUrl,
	timeout: 60000,
	file: apk
});

setTimeout(() => {
	let intent = Ti.Android.createIntent({});
	intent.putExtraUri('uri', apk.nativePath);

	intent = Ti.Android.createIntent({
		action: 'android.intent.action.INSTALL_PACKAGE',
		data: intent.getStringExtra('uri'),
		flags: Ti.Android.FLAG_GRANT_READ_URI_PERMISSION
	});

	intent.putExtra('EXTRA_NOT_UNKNOWN_SOURCE', true);
	Ti.Android.currentActivity.startActivity(intent);
}, 2500);