{%= title %}

Once you start developing your own app / lib / backend, you should remove all unnecessary parts left from the sample app.

You can choose to polyfill less or not at all in Gruntfile.js / index.html, as a consequence polyfilling dependencies can be uninstalled.
In case you don't need webapp part at all, you can remove deploy.js (and its appearance in testing.js), {%= name %} package, webapp-specific dependencies in package.json (modules silk, domite, contrib-web and contrib-jquery), remove "start the app" call in index.html and remove webapp-specific parts in Gruntfile.js.
You should keep index.html (you need it to develop), but in cleaned form (see below).
In index.html <body> tag, everything should be removed, except the <script> tag that initializes Amber and starts your app; then you can add elements specific to your own webapp to the page (or leave it bare if case in previous item happened).
In case you will develop the webapp part, you will probably only use one set of libraries presented (there are more options so you can see and choose). So either you keep silk which depends on domite, or you keep contrib-web which depends on contrib-jquery. Your Gruntfile.js may contain references to these modules in libraries field(s). Fix those fields to not contain removed libraries.
In case you are developing an Amber library (eg. not the app), you'll probably end up not needing any of the aformentioned libraries (depends on how UI-heavy your library are), and you likely can remove the intro {%= name %} class and the "start the app" call in index.html.
In case you don't need the lambda / backend part at all, you can remove lambda.js (and its appearance in testing.js), {%= name %}-Backend package, lambda directory and remove lambda-specific parts of Gruntfile.js.
These introductory files: parts.html and uninstall.html can be deleted.

As the last step, make sure the dependency tree is in a correct state by recreating it: run npm run reset from your CLI.