Custom software

Custom software (also known as bespoke software or tailor-made software) is software that is specially developed for some specific organization or other user. As such, it can be contrasted with the use of software packages developed for the mass market, such as commercial off-the-shelf (COTS) software, or existing free software.

Since custom software is developed for a single customer it can accommodate that customer's particular preferences and expectations. Custom software may be designed in stage by stage processes, allowing all nuances and possible hidden dangers to be taken into account, including issues which were not mentioned in the specifications. Especially the first phase in the software development process may involve many departments, including marketing, engineering, research and development and general management.

Large companies commonly use custom software for critical functions, including content management, inventory management, customer management, human resource management, or otherwise to fill the gaps present in the existing software packages. Often such software is legacy software, developed before COTS software packages offering the required functionality became available.

Custom software development is often considered expensive compared to off-the-shelf solutions or products. This can be true if one is speaking of typical challenges and typical solutions. However, it is not always true; custom software development by a reputable supplier is often a matter of building a house upon a solid foundation and, if managed properly, it is possible to do this quickly and to a high standard. In many cases, COTS software requires customization to correctly support the buyer's operations. The cost and delay of COTS customization frequently adds up to the expense of developing custom software.

Additionally, COTS comes with high upfront license costs frequently running into millions of dollars. Thus only the big corporations are able to absorb such high costs upfront. Additionally, the big software houses having COTS products revamp their product very frequently. Thus a particular implementation needs to be upgraded for compatibility every 2–4 years. Given the cost of customization, such upgrades also turn out to be expensive as a dedicated product release cycle will have to be earmarked for it.

The decision to build a custom software or go for a COTS implementation would usually reside on one or more of the following:

1. Finances - Cost and Benefit: The upfront license cost for COTS products mean that a thorough cost-benefit analysis of the business case needs to be done.
2. Time to market: COTS products usually have a lesser time to market.
3. Size of implementation: COTS comes with standardization of business processes and reporting. For a global and national player, these bring in gains in cost savings, efficiency and productivity.

Major fields

Construction

The construction industry uses custom software to manage projects, track changes, and report progress. Depending on the project, the software is modified to suit the particular needs of a project owner, the design team, and the general and trade contractors. For example, floor plans for a particular project are unique to that project and are available on mobile devices for the project team to consume through custom software. In some cases, the floor plans use SVG. Rooms and spaces on floor plans that use SVG are programmable; a room's fill color can change to red for instance if the room has outstanding deficiencies.

Project-specific data is used in other ways to suit the unique requirements of each project. Custom software accommodates a project team's particular preferences and expectations, making it suitable for most construction processes and challenges:

• design development
• tender calls
• document control
• shop drawing approvals
• changes management
• inspections and commissioning
• way-finding

Custom software developers use various platforms, like FileMaker, to design and develop custom software for the construction industry and for other industries.

Hospitals

Hospitals can keep the data of a patient and retrieve it any time. This enables a doctor and his assistants to transfer the details of a patient through a network. Keeping patients' blood groups in the hospital database makes the search for suitable-group blood easy. Hospitals also use billing software especially in their dispensary.

Places of Education

Schools use custom software to keep admission details of students. They produce Transfer Certificate also. Some governments develop special software for all of their schools. Sampoorna is a school management system project implemented by the Education Department of Government of Kerala, India to automate the system and process of over 15,000 schools in the state. These projects brings a uniformity for the schools.

Shops

Billing is a common use of custom software. Custom software is used by small shops, super markets and wholesale-sellers to handle stock-details and to generate bills.

Major project successes

This is a dynamic list and may never be able to satisfy particular standards for completeness. You can help by expanding it with reliably sourced entries.

Successful technology businesses based on custom software, such as Facebook, are not included on this list.

• FixMyStreet

Major project overruns and failures

Main article: List of failed and overbudget custom software projects

Failures and cost overruns of government IT projects have been extensively investigated by UK Members of Parliament and officials; they have had a rich seam of failures to examine, including:

• The NHS National Programme for IT
• Rural Payments Agency computer systems. On 15 March 2006 the Chief Executive Johnson McNeil was sacked when a deadline of 14 February for calculating Single Payment Scheme entitlements was missed.
• Universal Credit - the first trial could not even perform the most basic functions correctly; behind schedule and reportedly the project has been restarted.
• 1992 - LASCAD - the London Ambulance Service's new computer-aided despatch system - temporary crashes causing delays in routing ambulances. A previous attempt to develop a custom despatch system for the London Ambulance Service had also been scrapped.

Advantages and disadvantages

When a business is considering a software solution the options are generally between creating a spreadsheet (which is often done in Microsoft Excel), obtaining an off-the-shelf product, or having custom software created specifically to meet their needs. There are five main criteria involved in selecting the correct solution:

Criterion	Nature
Development cost and time	Quantitative
Other staff costs	Quantitative
System efficiency	Quantitative
Service improvement	Qualitative
Flexibility	Qualitative

Although initial assessments of the options according to these criteria may deviate sharply from the reality of the eventual solution when put into practice, due to factors such as cost overruns, insufficient training, poor product fit, reliability of the solution, etc.

These factors need to take into account the running of the business, it's industry, size and turnover. As such the decision can only be made on a business-by-business basis to determine if it warrants a custom development, as well as ownership of the software.

Advantages

Custom software will generally produce the most efficient system as it is can provide support for the specific needs of the business, which might not be available in an off-the-shelf solution and will provide greater efficiency or better customer service.

Given a suitable approach to development, such as DSDM, custom software will also produce the best or most well-targeted service improvement. Businesses can tailor the software to what their customers want instead of having to choose a package that caters for a generic market. For example one printing business may want software that responds in the shortest time, whereas another printing company may focus on producing the best results, as these two objectives often conflict an off-the-shelf package will normally sit somewhere in the middle whereas with custom software each business can focus on their target audience.

Although not always the most suitable for larger or more complex projects, a spreadsheet allows less technical staff at a business to modify the software directly and get results faster. Custom software can be even more flexible than spreadsheets as it is constructed by software professionals that can implement functionality for a wide range of business needs.

Disadvantages

The main disadvantages of custom software are development time and cost. With a spreadsheet or an off-the-shelf software package, a user can get benefits quickly. With custom software, a business needs to go through a Software development process that may take weeks, months, or with bigger projects, years. Bugs accidentally introduced by software developers, and thorough testing to iron out bugs, may impede the process and cause it to take longer than expected. However, spreadsheets and off-the-shelf software packages may also contain bugs, and moreover because they may be deployed at a business without formal testing, these bugs may slip through and cause business-critical errors.

Custom software is often several times the cost of the other two options, and will normally include an ongoing maintenance cost. This will often make custom software infeasible for smaller businesses. These higher costs can be insignificant in larger businesses where small efficiency increases can relate to large labour cost savings or where custom software offers a large efficiency boost.

Hybrid model

Particularly with modern cloud software, a hybrid model of custom software is possible in which the main software is off-the-shelf, but extensions or customisations are performed as custom software projects or mini-projects. This is the standard approach used when implementing SAP ERP, for example.