diff --git a/README.md b/README.md
index 792067e1..ce73706e 100644
--- a/README.md
+++ b/README.md
@@ -1,113 +1,47 @@
-# Create a JavaScript Action using TypeScript
+# Sign Android Release Action
 
-Use this template to bootstrap the creation of a JavaScript action.:rocket:
+This action will help you sign an Android `.apk` or `.aab` (Android App Bundle) file for release.
 
-This template includes compilication support, tests, a validation workflow, publishing, and versioning guidance.  
+## Inputs
 
-If you are new, there's also a simpler introduction.  See the [Hello World JavaScript Action](https://github.com/actions/hello-world-javascript-action)
+### `releaseDirectory`
 
-## Create an action from this template
+**Required:** The relative directory path in your project where your Android release file will be located
 
-Click the `Use this Template` and provide the new repo details for your action
+### `signingKeyBase64`
 
-## Code in Master
+**Required:** The base64 encoded signing key used to sign your app
 
-Install the dependencies  
-```bash
-$ npm install
-```
+### `alias`
 
-Build the typescript
-```bash
-$ npm run build
-```
+**Required:** The alias of your signing key 
 
-Run the tests :heavy_check_mark:  
-```bash
-$ npm test
+### `keyStorePassword`
 
- PASS  ./index.test.js
-  ✓ throws invalid number (3ms)
-  ✓ wait 500 ms (504ms)
-  ✓ test runs (95ms)
+**Required:** The password to your signing keystore
 
-...
-```
+### `keyPassword`
 
-## Change action.yml
+**Required:** The private key password for your signing keystore
 
-The action.yml contains defines the inputs and output for your action.
+## Outputs
 
-Update the action.yml with your name, description, inputs and outputs for your action.
+### `signedReleaseFile`
 
-See the [documentation](https://help.github.com/en/articles/metadata-syntax-for-github-actions)
+The path to the signed release file from this action
 
-## Change the Code
+### ENV: `SIGNED_RELEASE_FILE`
 
-Most toolkit and CI/CD operations involve async operations so the action is run in an async function.
+This also set's an environment variable that points to the signed release file
 
-```javascript
-import * as core from '@actions/core';
-...
-
-async function run() {
-  try { 
-      ...
-  } 
-  catch (error) {
-    core.setFailed(error.message);
-  }
-}
-
-run()
-```
-
-See the [toolkit documentation](https://github.com/actions/toolkit/blob/master/README.md#packages) for the various packages.
-
-## Publish to a distribution branch
-
-Actions are run from GitHub repos.  We will create a releases branch and only checkin production modules (core in this case). 
-
-Comment out node_modules in .gitignore and create a releases/v1 branch
-```bash
-# comment out in distribution branches
-# node_modules/
-```
-
-```bash
-$ git checkout -b releases/v1
-$ git commit -a -m "prod dependencies"
-```
-
-```bash
-$ npm prune --production
-$ git add node_modules
-$ git commit -a -m "prod dependencies"
-$ git push origin releases/v1
-```
-
-Your action is now published! :rocket: 
-
-See the [versioning documentation](https://github.com/actions/toolkit/blob/master/docs/action-versioning.md)
-
-## Validate
-
-You can now validate the action by referencing the releases/v1 branch
+## Example usage
 
 ```yaml
-uses: actions/typescript-action@releases/v1
+uses: actions/sign-android-release@v1
 with:
-  milliseconds: 1000
-```
-
-See the [actions tab](https://github.com/actions/javascript-action/actions) for runs of this action! :rocket:
-
-## Usage:
-
-After testing you can [create a v1 tag](https://github.com/actions/toolkit/blob/master/docs/action-versioning.md) to reference the stable and tested action
-
-```yaml
-uses: actions/typescript-action@v1
-with:
-  milliseconds: 1000
-```
+  releaseDirectory: /app/build/outputs/apk/release
+  signingKeyBase64: ${{ secrets.SIGNING_KEY }}
+  alias: ${{ secrets.ALIAS }}
+  keyStorePassword: ${{ secrets.KEY_STORE_PASSWORD }}
+  keyPassword: ${{ secrets.KEY_PASSWORD }}
+```
\ No newline at end of file
diff --git a/action.yml b/action.yml
index 5cfdde4b..07384091 100644
--- a/action.yml
+++ b/action.yml
@@ -1,10 +1,28 @@
-name: 'Your name here'
-description: 'Provide a description here'
-author: 'Your name or organization here'
+name: 'Drew Heavner'
+description: 'An action to sign an Android release APK or AAB'
+author: 'r0adkll'
+branding:
+  icon: 'edit'
+  color: 'orange'
 inputs:
-  myInput:              # change this
-    description: 'input description here'
-    default: 'default value if applicable'
+  releaseDirectory:
+    description: 'The directory to find your release to sign'
+    required: true
+  signingKeyBase64:
+    description: 'The key used to sign your release in base64 encoded format'
+    required: true
+  alias:
+    description: 'The key alias'
+    required: true
+  keyStorePassword:
+    description: 'The password to the keystore'
+    required: true
+  keyPassword:
+    description: 'The password for the key'
+    required: true
+outputs:
+  signedReleaseFile:
+    description: 'The signed release APK or AAB file'
 runs:
   using: 'node12'
   main: 'lib/main.js'
diff --git a/package-lock.json b/package-lock.json
index 3c556ab4..60c26f4a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
-  "name": "node12-template-action",
-  "version": "0.0.0",
+  "name": "sign-android-release",
+  "version": "1.0.0",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -9,6 +9,11 @@
       "resolved": "https://registry.npmjs.org/@actions/core/-/core-1.0.0.tgz",
       "integrity": "sha512-aMIlkx96XH4E/2YZtEOeyrYQfhlas9jIRkfGPqMwXD095Rdkzo4lB6ZmbxPQSzD+e1M+Xsm98ZhuSMYGv/AlqA=="
     },
+    "@actions/exec": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@actions/exec/-/exec-1.0.1.tgz",
+      "integrity": "sha512-nvFkxwiicvpzNiCBF4wFBDfnBvi7xp/as7LE1hBxBxKG2L29+gkIPBiLKMVORL+Hg3JNf07AKRfl0V5djoypjQ=="
+    },
     "@babel/code-frame": {
       "version": "7.5.5",
       "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.5.5.tgz",
@@ -1080,9 +1085,9 @@
       }
     },
     "commander": {
-      "version": "2.20.0",
-      "resolved": "https://registry.npmjs.org/commander/-/commander-2.20.0.tgz",
-      "integrity": "sha512-7j2y+40w61zy6YC2iRNpUe/NwhNyoXrYpHMrSunaMG64nRnaf96zO/KMQR4OyN/UnE5KLyEBnKHd4aG3rskjpQ==",
+      "version": "2.20.3",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-2.20.3.tgz",
+      "integrity": "sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==",
       "dev": true,
       "optional": true
     },
@@ -2293,9 +2298,9 @@
       "dev": true
     },
     "handlebars": {
-      "version": "4.1.2",
-      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.1.2.tgz",
-      "integrity": "sha512-nvfrjqvt9xQ8Z/w0ijewdD/vvWDTOweBUm96NTr66Wfvo1mJenBLwcYmPs3TIBP5ruzYGD7Hx/DaM9RmhroGPw==",
+      "version": "4.5.1",
+      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.5.1.tgz",
+      "integrity": "sha512-C29UoFzHe9yM61lOsIlCE5/mQVGrnIOrOq7maQl76L7tYPCgC1og0Ajt6uWnX4ZTxBPnjw+CUvawphwCfJgUnA==",
       "dev": true,
       "requires": {
         "neo-async": "^2.6.0",
@@ -4936,13 +4941,13 @@
       "dev": true
     },
     "uglify-js": {
-      "version": "3.6.0",
-      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.6.0.tgz",
-      "integrity": "sha512-W+jrUHJr3DXKhrsS7NUVxn3zqMOFn0hL/Ei6v0anCIMoKC93TjcflTagwIHLW7SfMFfiQuktQyFVCFHGUE0+yg==",
+      "version": "3.6.8",
+      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.6.8.tgz",
+      "integrity": "sha512-XhHJ3S3ZyMwP8kY1Gkugqx3CJh2C3O0y8NPiSxtm1tyD/pktLAkFZsFGpuNfTZddKDQ/bbDBLAd2YyA1pbi8HQ==",
       "dev": true,
       "optional": true,
       "requires": {
-        "commander": "~2.20.0",
+        "commander": "~2.20.3",
         "source-map": "~0.6.1"
       }
     },
diff --git a/package.json b/package.json
index 9e198988..eac9553d 100644
--- a/package.json
+++ b/package.json
@@ -1,8 +1,8 @@
 {
-  "name": "typescript-action",
-  "version": "0.0.0",
+  "name": "sign-android-release",
+  "version": "1.0.0",
   "private": true,
-  "description": "TypeScript template action",
+  "description": "GitHub action used to sign Android release packages",
   "main": "lib/main.js",
   "scripts": {
     "build": "tsc",
@@ -10,17 +10,18 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/actions/typescript-action.git"
+    "url": "git+https://github.com/r0adkll/sign-android-release.git"
   },
   "keywords": [
     "actions",
     "node",
     "setup"
   ],
-  "author": "YourNameOrOrganization",
+  "author": "r0adkll",
   "license": "MIT",
   "dependencies": {
-    "@actions/core": "^1.0.0"
+    "@actions/core": "^1.0.0",
+    "@actions/exec": "^1.0.1"
   },
   "devDependencies": {
     "@types/jest": "^24.0.13",
diff --git a/src/io-utils.ts b/src/io-utils.ts
new file mode 100644
index 00000000..04f4b158
--- /dev/null
+++ b/src/io-utils.ts
@@ -0,0 +1,14 @@
+import {Dirent} from "fs";
+
+const path = require('path');
+const fs = require('fs');
+
+export function findReleaseFile(releaseDir: string): Dirent | undefined {
+    const releaseFiles = fs.readdirSync(releaseDir, {withFileTypes: true})
+        .filter(item => !item.isDirectory())
+        .filter(item => item.name.endsWith(".apk") || item.name.endsWith(".aab"));
+
+    if (releaseFiles.length > 0) {
+        return releaseFiles[0]
+    }
+}
\ No newline at end of file
diff --git a/src/main.ts b/src/main.ts
index 191f3882..c3254e8d 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -1,16 +1,48 @@
 import * as core from '@actions/core';
 import {wait} from './wait'
+import {signAabFile, signApkFile} from "./signing";
+const path = require('path');
+const fs = require('fs');
+const io = require('io-utils');
+const sign = require('signing');
 
 async function run() {
   try {
-    const ms = core.getInput('milliseconds');
-    console.log(`Waiting ${ms} milliseconds ...`)
+    const releaseDir = core.getInput('releaseDirectory');
+    const signingKeyBase64 = core.getInput('signingKeyBase64');
+    const alias = core.getInput('alias');
+    const keyStorePassword = core.getInput('keyStorePassword');
+    const keyPassword = core.getInput('keyPassword');
 
-    core.debug((new Date()).toTimeString())
-    await wait(parseInt(ms, 10));
-    core.debug((new Date()).toTimeString())
+    console.log(`Preparing to sign key @ ${releaseDir} with signing key`);
 
-    core.setOutput('time', new Date().toTimeString());
+    // 1. Find release file
+    const releaseFile = io.findReleaseFile(releaseDir);
+    if (releaseFile !== undefined) {
+      core.debug(`Found release to sign: ${releaseFile.name}`);
+
+      // 2. Now that we have a release file, decode and save the signing key
+      const signingKey = path.join(releaseDir, 'signingKey.jks');
+      fs.writeFileSync(signingKey, signingKeyBase64, 'base64');
+
+      // 3. Now zipalign the release file
+      const releaseFilePath = path.join(releaseDir, releaseFile.name);
+      let signedReleaseFile = '';
+      if (releaseFile.name.endsWith('.apk')) {
+        signedReleaseFile = await signApkFile(releaseFilePath, signingKey, alias, keyStorePassword, keyPassword);
+      } else if (releaseFile.name.endsWith('.aab')) {
+        signedReleaseFile = await signAabFile(releaseFilePath, signingKey, alias, keyStorePassword, keyPassword);
+      } else {
+        core.error('No valid release file to sign, abort.');
+        core.setFailed('No valid release file to sign.');
+      }
+
+      core.exportVariable("SIGNED_RELEASE_FILE", signedReleaseFile);
+      core.setOutput('signedReleaseFile', signedReleaseFile);
+    } else {
+      core.error("No release file (.apk or .aab) could be found. Abort.")
+      core.setFailed('No release file (.apk or .aab) could be found.');
+    }
   } catch (error) {
     core.setFailed(error.message);
   }
diff --git a/src/signing.ts b/src/signing.ts
new file mode 100644
index 00000000..ae20b03a
--- /dev/null
+++ b/src/signing.ts
@@ -0,0 +1,53 @@
+import * as exec from '@actions/exec';
+import * as core from '@actions/core';
+
+export async function signApkFile(
+    apkFile: string,
+    signingKeyFile: string,
+    alias: string,
+    keyStorePassword: string,
+    keyPassword: string
+): Promise<string> {
+
+    core.debug("Zipaligning APK file");
+
+    // Align the apk file
+    const alignedApkFile = apkFile.replace('.apk', '-aligned.apk');
+    await exec.exec('zipalign', [
+        '-v', '-p 4',
+        apkFile,
+        alignedApkFile
+    ]);
+
+    core.debug("Signing APK file");
+
+    // apksigner sign --ks my-release-key.jks --out my-app-release.apk my-app-unsigned-aligned.apk
+    const signedApkFile = apkFile.replace('.apk', '-signed.apk');
+    await exec.exec('apksigner', [
+        'sign',
+        '--ks', signingKeyFile,
+        '--out', signedApkFile,
+        alignedApkFile
+    ]);
+
+    return signedApkFile
+}
+
+export async function signAabFile(
+    aabFile: string,
+    signingKeyFile: string,
+    alias: string,
+    keyStorePassword: string,
+    keyPassword: string
+): Promise<string> {
+    core.debug("Signing AAB file");
+    await exec.exec(`jarsigner`, [
+        '-keystore', signingKeyFile,
+        '-storepass', keyStorePassword,
+        '-keypass', keyPassword,
+        aabFile,
+        alias
+    ]);
+
+    return aabFile
+}
\ No newline at end of file