Similarly to the cost of development, there’s no definitive answer to how long it will take to build a certain product. The process of app development for construction can take a couple of months, or it can last for a couple of years—it depends on how many unique features you need and how much data will be involved. With projects with typical functionality—such as scheduling, accounting, project management, etc.—you can expect to have one completed in 2-6 months, especially if you partner with a flexible outsourcing company. But if you require complex IoT connections or AR/VR visualizations, you should expect to have a longer process of development.