Build or buy an event app

Two very different people search this question. One is an event organizer working out whether a developer friend could knock something together before March. The other is a developer scoping a client project. This guide is written for the first, with enough engineering specificity to be useful to the second.

If you are the organizer: the short answer is that building is almost never cheaper for a single conference, and the reason has nothing to do with the first version. It is the second year.

What “build” actually contains

A conference app is deceptively small at the surface and unusually broad underneath. The screens are simple. The systems behind them are not.

Component	Why it is harder than it looks
Schedule and personal agenda	Time zones, multi-day, sessions that move, and a saved agenda that must update when they do
Attendee directory and profiles	Privacy controls, opt-out, moderation, and a search that stays fast at 3,000 rows
Push notifications	Certificates, tokens, per-platform delivery, deep links into specific screens, and delivery reporting
Live Q&A and polls	Real-time fan-out, moderation before display, and behaviour when the venue Wi-Fi degrades
Photo album	Uploads, storage, moderation, reporting, and a viewer that does not exhaust memory on older phones
Organizer console	A second application, with roles, an audit trail and bulk import
Auth and invites	Claim links, expiry, re-issue, and the account-recovery path someone will need at 8am on day one
Store presence	Two developer accounts, two review processes, two sets of screenshots and privacy declarations

Every one of these is a week of work as a demo and a month as a product. The organizer console is the item most often left out of the estimate entirely, and it is roughly a third of the total.

A realistic build estimate

For a first version that could carry a real 500-person conference:

Phase	Engineering months
Schedule, sessions, personal agenda	1.5
Attendee directory, profiles, connections	1.0
Push notification pipeline, both platforms	1.0
Live Q&A, polls, moderation	1.5
Organizer console with roles and import	2.0
Auth, invites, account recovery	0.5
Store submission, both platforms	0.5
Testing on real devices and a rehearsal	1.0
Total	9.0

You can compress this to about six months by cutting live engagement and shipping web-only, which removes the store submissions and roughly half the platform-specific work. That is a legitimate scope decision, and it is also the point at which you have built a mobile-friendly event website rather than an event app.

The hard, non-negotiable costs are small and boring: an Apple Developer Program membership at $99 per year, a one-time $25 Google Play developer registration, and a domain. The expensive part is people.

The part everyone under-estimates

Push notifications. The demo is an afternoon. The product is a month. Certificates expire, tokens go stale when an attendee reinstalls, the two platforms disagree about what happens when the app is backgrounded, and a deep link that opens the app’s home screen instead of the session that moved is worse than sending nothing. Then there is delivery reporting, which organizers ask for immediately and which nobody builds in version one.

Session capacity. If capacity is enforced in the app rather than on the server, two attendees on two phones will both take the last seat in a workshop. Fixing it after the fact is a conversation with a room of forty people and eight chairs.

The event-day failure mode. A conference app has a load profile unlike almost anything else: nothing for months, then every attendee opens it within a ten-minute window at registration. A system that has never seen that pattern will meet it for the first time in front of your attendees.

The cost that never stops

This is the number that decides the question, and it is absent from most build estimates.

• Two operating-system releases a year. iOS and Android both ship a major version annually. Each can change layout, permissions or notification behaviour. Somebody tests and patches, whether or not you have an event that year.
• Dependency and security updates. A mobile app is a dependency tree. Leaving it unattended for eighteen months is how a small update becomes a rewrite.
• Certificate and provisioning renewals. Push certificates and provisioning profiles expire. When they do, notifications stop, silently.
• Store policy changes. Privacy declarations and data-handling disclosures have changed materially more than once. Each change is a resubmission.
• Someone on call. During every event, for the life of the app.

Over three years, maintenance typically exceeds the original build. That is the whole argument, and it is why the comparison should be run over three years rather than one.

The comparison, over three years

Assume one 600-person conference a year.

	Build	Licence
Year 1	9 engineering months, plus $99 and $25 in developer fees	$2,750 on event67 (550 billable at $5)
Year 2	Maintenance, OS releases, one certificate scare	$2,750
Year 3	Maintenance, plus whatever version two costs	$2,750
Three-year total, excluding salaries	Roughly $300 in fees, plus the engineering	$8,250
Who is on call during the event	You	The vendor
Who handles the next OS release	You	The vendor

Put the engineering cost at whatever your organization actually pays, and the arithmetic resolves itself in almost every case. At event67’s published prices, three years of a 600-person conference costs less than one engineering month at a typical North American contract rate.

When building genuinely is right

There are real cases. Building wins when the app is the product rather than a support tool for one week a year:

• A year-round community app where the conference is one feature among many, and engagement continues in the other fifty weeks.
• A proprietary content or credentialing model that no vendor supports, and that is itself a reason members join.
• A regulatory or data-residency requirement that no available vendor can meet, verified rather than assumed.
• An integration so specific it is the point of the app — a manufacturing floor plan, a clinical scheduling system, a members’ database with rules no import can express.

Note what is not on that list: wanting your own branding, wanting the app to feel like yours, or wanting control over the schedule. Every one of those is available under a licence, and branded native apps published under your own name are the normal product in this market rather than a premium tier.

A middle path worth knowing about

There is a third option that neither camp advertises, and for a minority of organizers it is the right one: license the app and build only the one thing that is genuinely yours.

That means taking a product for the schedule, the directory, the notifications and the live engagement, and building a small integration or a single custom surface against whatever makes your event unusual — a members database with rules no import can express, a manufacturing floor plan, a scheduling system that owns the source of truth.

The economics are much better than a full build because the expensive parts of the list above are exactly the parts you are not building. The store submission, the notification pipeline, the moderation queues and the two operating-system releases a year all stay with the vendor.

The thing to check before committing is whether the product you license has a way in. Ask for an API or a webhook by name, ask which objects it exposes, and ask whether it is on the plan you are buying rather than the one above it. Several products in this market publish integrations only on higher tiers, which turns a small piece of engineering into a licence upgrade.

Be honest that this is still a build. It needs an owner, it needs maintaining, and it will break when either side changes. It is simply a much smaller one, aimed at the part of your event that is actually distinctive rather than at the part every conference shares.

If you build anyway

Some advice worth more than it costs:

1. Build the organizer console first. It is the part you will use most and the part demos always skip.
2. Enforce capacity on the server. Always. No exceptions.
3. Ship the web version before the native apps. It de-risks content and gives you a fallback if a store review goes badly.
4. Rehearse the load. Simulate 600 people opening the app in ten minutes, before the day 600 people do.
5. Write the runbook. Who is called, on what number, when notifications stop during a keynote.
6. Budget the second year now, in the same document, or the decision is being made on half the number.