Lorry, if you have little knowledge of application development and programming languages, then you can try app development platforms where low-code or no-code is required to build applications. Back4App, Backendless and BuildFire could be good options in this regard. Likewise, you just need to signup on BuildFire, and their drag and drop interface will guide you everything about building, designing and launching your applications.
On the other hand, if your requirement is custom app development, then you should surely hire a good company. I can suggest Purple Crane in this regard because I found them very cost-efficient and fast when it comes to custom app development. Actually, my London-based friend referred
this source to me to get a review. I wasn't familiar with their services. That is why I started from a test job, and it was an API integration. They perfectly did the job, and now, I am working with them on my 3 office applications. You can also try their services.
In the same token, you can also search local or international app development companies on GoodFirms and pick one according to your needs.
There are no shortcuts in Life.