There are several things you should organise before you even approach, talk to and hire app developers. These are your requirements, a budget and pricing model you are comfortable with.

In order to find a good app developer, you need to see if they are experienced or know about app development in your particular industry or business model. This is crucial as many people with app ideas but without technical knowledge ends up paying a hefty sum, wasting time or ending up with a subpar app riddled with bugs.  
 
Apart from testing out previous apps they have done, look at how responsive, attentive and invested they are in learning about your idea and business. They should be transparent about their processes and work and can meet realistic milestones. And never ignore the importance of support services because there are no apps created without bugs; good app developers just create fewer bugs or issues than mediocre ones.

Hi, I would suggest you understand the capability of the app developers. Analyze whether they are capable of understanding all your business requirements and also they are able to provide creative solutions in building mobile apps. Analyze their experience and skills. 

Here is a list of top mobile app development companies from where you can hire developers
1. The app team (https://www.theappteam.com.au/)
2. Fortunesoft IT Innovations (https://www.fortunesoftit.com/au/mobile-app-development-company-australia/)
3. app square (https://www.appsquare.com.au/)

Whether you’re outsourcing overseas, hiring locally or employing an in-house app developer, there are some key traits that all good app developers share. Transparency, good communication skills, teamwork and a strong portfolio are just a few.

Outsourcing is a great option for many business owners as it’s often cheaper, more flexible and gives you access to a wider pool of talent. But of course, it comes with unique risks and considerations. Some key considerations when outsourcing an app developer (either locally or overseas) include:

1. Money-back guarantee - choose a developer that provides a money-back guarantee or revision policy. Make sure this is clearly outlined in the contract before you sign anything.

2. Cost breakdown - a good app developer will provide a breakdown of the project costs including any additional charges like GST. There should be no surprises when you pay your final invoices.

3. Avoid app developers who request you to pay large sums of money upfront - there should be an initial cost to pay, but the rest should be paid in milestones or when the final work is delivered.

4. Adequate experience - your developer should have the skills and experience to deliver your project outline. Have they worked on similar projects or with similar businesses? These are important questions to ask.

5. Time zone differences - outsourcing a developer may mean you are working in different time zones. Decide whether this will be a barrier for you before you begin your search.

6. Great communications skills - a good developer will run you through the project plan and be clear on how they will communicate with you. This is partly your responsibility to set clear expectations on how you want to be involved across the project from the beginning.

7. Cheapest isn't always best - no matter which service you’re looking for, it’s often a case of ‘you get what you pay for’. Don’t be tempted to go for the lowest quote before doing your research and reviewing a developer’s portfolio.