There are different terminologies used in Agile methodology in a product lifecycle, out of which the evaluation period and duration overall play an important role. This is where Sprint, Iteration, and Increment come into the picture. Development cycles help us to understand what needs fixing before adding another item on top of everything that has been done up till now. The article focuses on discussing the difference between sprint, iteration, and increment.

What is Sprint?

Sprint is a single time-boxed iteration of a continuous development cycle achieving better results rather quickly. Here the team has to complete all the planned work within a designated time frame and prepare it for review. 
For example, the iOS development team at Apple Inc. typically operates under a schedule of two weeks with a specific goal of completing 20 applications per team member. Each application has a name derived from its sprint name and number (e.g., iOS 10 Summer 2017). During each sprint, members focus on developing a certain feature while avoiding bugs and other problems that could delay completion. Once an application is completed, it undergoes testing before being approved for release by the company’s leadership team. After approval, the application is released to the public for use on Apple devices. 

Characteristics of Sprint

• Establishes a Work-in-Progress Limit: A work-in-progress task is one that began but did not finish. In traditional project management, there was a long list of such work items that had been pending for months. Failure to manage these WIP tasks can have serious consequences for budget, quality, and timelines. Because Sprints are timeboxed, these WIP tasks cannot exceed their duration. Only work that the team is confident of completing within the Sprint will be selected.
• Prioritization of the Forces: Because Scrum is iterative, we get to choose what work needs to be completed each Sprint. It would occur every 1-4 weeks, depending on the length of the Sprint. It causes the Scrum team to prioritize their work.
• Avoids Work Gold Plating: Gold Plating entails purposefully including features that were not originally planned. It frequently pleases the clients. 

What is Iteration?

Iteration involves an extended period of time with slight modifications to the original plan. There are still risks when starting from scratch, but as long you get into a position where your goals can be met and if there is enough spare capacity in each iteration then things move quickly. For example, If the initial development project begins now and iteration is tried out for only two weeks before moving on to building more complex systems then there will be no problems in that case since all these tests are done using the JUnit testing framework directly which can detect errors without much effort but if you start off slowly or introduce new features too quickly after some minor work-in-progress changes they have probably already started failing as well. 

Another example, in addition to bug fixes and new feature development, Android development teams also make minor modifications after each iteration. Each minor modification occurs based on user feedback during regular user testing sessions. During each iteration, developers focus on one or more specific areas they wish to improve while mitigating any unexpected issues that may arise. Once improvements are complete, developers test their work again before submitting any changes to the management team for approval- at which point it becomes ‘release.’

Characteristics of iteration

• Follow calendar weeks: Iteration follows calendar weeks starting on Mondays and ending on Fridays.
• Fixed length iterations: the fixed length of iteration helps the development teams to get an accurate estimate of how long it takes until the project is completed.
• Short iterations: The short iterations are intended to manage uncertainty and associated risk. This short period helps the product managers’ stakeholders to frequently evaluate technical and business hypotheses in the system.

When choosing the duration for the iteration, one should consider how well the team is familiar and comfortable with agile methodology. The teams that are new to agile methodology should begin with longer iteration, on the other hand those that are familiar with agile methodology can begin with shorter iterations. 

What is Increment?

The increment involves small changes made during each iteration to improve existing features or fix bugs without delay. When working on any project, it’s important to know what your goals are so that you can work towards them effectively. Setting concrete goals helps you stay focused while working towards your desired end results.  Additionally, understanding when and how to modify your plans helps you stay on track and meet your deadlines with expert craftsmanship.

Sprint vs Iteration vs Increment 

The Below table gives the major difference between Sprint, Iteration, and Increment.