Below are some of the favorite resources I use to help create an app and manage things online.  There's nothing "magical" about it nor complex.  These resources will help you get started building your app quickly.  If you're looking to start selling apps, these resources below will be invaluable!

INTERNET BASED RESOURCES

Google Chrome-Although the app building software is compatible with any web browser, Google Chrome is the browser that I choose to utilize.  

The SnagIt extension I use is an add on within Google Chrome.  This allows you to record a portion of your screen or the entire thing and do a direct upload to YouTube as well.  Currently, it's not possible to download it.  A similar functioning software is ShareX.  

Dropbox-This is perhaps one of the most well known cloud storage services.  This will allow you to store and share all types of files for yourself and for those whom you work with once they get permission.  Get started here.

LogoNerds is a simple way to have a logo made to support your website in very short order.  Submit your requirements and in 3-5 days you'll receive three different concepts to choose from starting at $27.  

Canva is the site if you want to get a photo featuring real people engaged in various activities.  Receive images for free or simply pay an amount as low as $1.  Here is the link for you to get started.  

Namecheap is the domain registrar of choice.  Although many web hosting companies will allow you to register a website name for free, they still ultimately own it.  When you elect to move to another host, it can be quite the hassle.  This will allow you move your website content to a new host and simply "point" the web address thus making things much easier for you.  

When you are looking to "get your feet wet" in building a website, Bluehost is perhaps the best company to work with.  Aside from one click WordPress installs, there's 24/7 customer support, nearly unlimited storage, daily website backups are just a few reasons to utilize this service.  

To build a website, one thing you need to do is make a great first impression to your visitors.  StudioPress is a great way to get a premium theme with a minimum price.  With six broad categories ranging from business to eCommerce containing over 100 themes, they will have what you need.  

When you are looking to promote your website with sales funnels, landing pages, and/or a membership portal, OptimizePress is an all in one package that will assist you in this endeavor.  Integrating seamlessly with WordPress, rest assured you'll have a webpage that's mobile responsive in very short order. 

App Building

When it comes to building an actual app, you can use the Mobile App Maker Pro App Building Guide to help assist you when you quickly build a mobile app for your small business or for others.  I'll show you how to connect various social media elements as well.  Here's some things that you can use on the internet to help you build an app in very short order.  

If you are trying to get the color scheme:

Image Color Picker: Upload your image and get the hex color code

Background Image Generator: Create color coded backgrounds. 

Website Color Combos: Grab the hex code of an entire website.