Android App - Improvements needed

Hello developers, I need someone to make improvements on a recently - completed Android app. Just need to fix a few features on my app...Right now if someone doesn't have a front camera it just crashes on load also it has no settings menu currently so i would like a settings menu to be implemented where someone can toggle sound effects off and maybe even change the background from the settings menu.. In your application, please provide links to Android apps you have completed previously. Please apply only if you are able to begin and complete the job within a day or two. Please do not send any attachments, as they will not be opened. Please feel free to ask any clarifying questions.