Salesforce Mobile Integration Services

Salesforce Integration with Mobile App

You are developing a mobile app for a sales team that needs to sync leads, contacts, opportunities, and cases with Salesforce. The standard approach via Salesforce Mobile SDK adds 15+ MB to the app size and ties you to the SDK, which is not always convenient. We offer flexible integration: from a lightweight REST client to full synchronization using Platform Events for real-time updates. Our team has 5+ years of experience in mobile development and CRM integration — we have delivered 20+ such turnkey projects.

Salesforce is a mature CRM platform with a well-documented REST API (developer.salesforce.com) and several mobile SDKs. Unlike 1C or Bitrix24, it has fewer unexpected API limitations, but more concepts to learn: Connected App, OAuth 2.0 flows, SOQL, SOSL, Apex REST, and Platform Events. We guarantee that the integration will comply with App Store Connect and Google Play Console guidelines.

How to Set Up Connected App and OAuth 2.0 for a Mobile App?

It all starts with creating a Connected App in Salesforce Setup: App Manager → New Connected App. Specify a Callback URL (the app's deeplink), enable OAuth scopes: api, refresh_token, offline_access.

The mobile app uses OAuth 2.0 Authorization Code Flow or JWT Bearer Flow for server-to-server communication. For user context, we use Authorization Code. We rely on proven libraries: AppAuth for Android and ASWebAuthenticationSession for iOS.

On Android with AppAuth:

val serviceConfig = AuthorizationServiceConfiguration(
    Uri.parse("https://login.salesforce.com/services/oauth2/authorize"),
    Uri.parse("https://login.salesforce.com/services/oauth2/token")
)

val request = AuthorizationRequest.Builder(
    serviceConfig,
    clientId,
    ResponseTypeValues.CODE,
    Uri.parse("myapp://oauth/callback")
).setScope("api refresh_token offline_access").build()

authService.performAuthorizationRequest(request, pendingIntent)

After exchanging the code for a token, we save access_token, refresh_token, and instance_url — the base URL for all API calls (each Salesforce org has its own subdomain).

REST API and SOQL: How to Fetch Data Efficiently?

REST API is the main interface. Base URL: {instance_url}/services/data/v60.0/. Choose the API version based on the minimum Salesforce API version your client supports.

An SOQL (Salesforce Object Query Language) request:

GET /services/data/v60.0/query/?
  q=SELECT+Id,Name,Amount,StageName,CloseDate,Account.Name
  +FROM+Opportunity
  +WHERE+OwnerId='{userId}'+AND+IsClosed=false
  +ORDER+BY+CloseDate+ASC+LIMIT+50

SOQL is SQL-like but with limitations: no JOIN in the usual sense; related objects via relationship queries (Account.Name). LIMIT max is 2000. For large datasets, use queryMore with the nextRecordsUrl from the response.

Creating a record: POST /services/data/v60.0/sobjects/Opportunity/ with JSON body. Updating: PATCH /services/data/v60.0/sobjects/Opportunity/{id}. Note: Salesforce uses PATCH, not PUT for updates.

Why Use Platform Events for Real-Time Updates?

Salesforce Platform Events is a publish/subscribe mechanism. The server publishes an event (OpportunityUpdated__e), clients receive it via CometD (Bayeux protocol, long polling).

val cometdClient = BayeuxClient(
    "${instanceUrl}/cometd/60.0",
    LongPollingTransport.create(null, okHttpClient)
)
cometdClient.handshake()
cometdClient.getChannel("/event/OpportunityUpdated__e")
    .subscribe { message ->
        val payload = message.dataAsMap
        handleOpportunityUpdate(payload)
    }

For one client, we reduced sync latency from 5 seconds to under 1 second using Platform Events and a custom CometD client, while keeping the APK size minimal.

Comparison of Integration Approaches

How to Upload Files to Salesforce from a Mobile App?

Files in Salesforce are ContentDocument and ContentVersion. Uploading a file from a mobile app:

POST /services/data/v60.0/sobjects/ContentVersion/
Content-Type: multipart/form-data

{
  "Title": "Customer photo",
  "PathOnClient": "photo.jpg",
  "FirstPublishLocationId": "{opportunityId}"
}
+ binary data

FirstPublishLocationId is the object to which the file is attached. Limitation: one file per request. For multiple files, use sequential requests or Salesforce Bulk API.

What Is Included in the Integration Work

1. Analysis of current CRM structure and sync requirements.
2. Configuration of Connected App and OAuth flows (Authorization Code / JWT Bearer).
3. Development of REST client with caching and error handling.
4. Integration of Platform Events for real-time notifications.
5. Testing on sandbox and production Salesforce orgs.
6. Documentation of API and deployment instructions.
7. Post-launch support (1 month).

Timelines and Pricing

Basic integration (OAuth, SOQL queries, CRUD for Opportunity/Contact): 1-2 weeks. Platform Events, offline caching, push notifications: additional 1-2 weeks. Full-featured app with Salesforce Mobile SDK, SmartStore, and synchronization: 1.5-2 months. Cost is calculated individually. Send us a request for an estimate.

How to Start Integrating API into a Mobile App?

The request goes out, the response doesn't come, timeout — 30 seconds. The user stares at the spinner. No network — mobile card in the subway. Or the network is there, but the server returns 200 with an HTML error page instead of JSON — and the app crashes on JSONDecoder.decode(). We see such cases on every second project. So integrating API into a mobile app is not just calling an endpoint, but designing a reliable network layer: error handling, caching, offline mode, certificate pinning. Order an audit of your current network layer — we will evaluate the project in 1 day. Our team guarantees a thorough analysis and provides a detailed roadmap.

Standard libraries like URLSession and OkHttp provide basic HTTP clients, but for production you need retries with exponential backoff, status code validation, typed deserialization, and network state monitoring. Without this, the app loses data and users. We have been doing mobile development for 5 years and implemented more than 30 projects with API integration on iOS, Android, and Flutter — from startups to enterprise solutions.

How to Choose a Protocol for API Integration?

REST remains the standard for most projects. But when a profile screen needs 5 fields out of 40, GraphQL eliminates over-fetching and reduces traffic by 30–60%. gRPC is justified for thousands of requests per minute (trading, IoT) — binary serialization is 3–5 times faster than JSON. WebSocket is the only choice for real-time without polling (messages, notifications).

Practical example: For a fintech app, we replaced REST (40 fields) with GraphQL — response size dropped from 12 KB to 2.5 KB, screen render time decreased by 70%. Traffic savings were significant. Our certified iOS and Android developers have deep experience with all these protocols — you can rely on proven solutions.

How to Ensure Reliable Connection and Offline-First?

Users lose network in the subway, elevator, tunnel. A mobile app must work without internet — at least in read-only mode. We implement the offline-first pattern:

1. On screen open, first show data from the local cache (Core Data / Room).
2. Simultaneously perform a network request, update UI after response.
3. If network is unavailable — show cached data and a 'no connection' label.
4. When network is restored, automatically synchronize changes.

For HTTP response caching we use URLCache (iOS) and OkHttp Cache (Android) with Cache-Control support. For structured data — SwiftData / Room. NWPathMonitor / ConnectivityManager.NetworkCallback monitor network state and trigger updates.

REST and Client Library Selection

Alamofire (iOS) — de facto standard for Swift projects. On top of URLSession it adds request chaining, response validation, automatic retry, certificate pinning via ServerTrustManager. AF.request() with .validate() returns an error for any status code outside 200–299. Without .validate(), Alamofire considers 404 and 500 as successful responses. With Swift Concurrency — async version via serializingDecodable.

Retrofit (Android) — annotation-based HTTP client on top of OkHttp. An interface with annotations compiles into implementation. @GET, @POST, @Path, @Query, @Body — declarative API description. OkHttp under the hood: connection pooling, transparent gzip, HTTP/2 multiplex. HttpLoggingInterceptor — logging in debug builds. Authenticator — automatic token refresh on 401.

Ktor (KMM/Flutter) — multiplatform HTTP client. On iOS it works via Darwin engine (URLSession), on Android — via OkHttp. Single code for both platforms with KMM architecture.

GraphQL: When REST Falls Short

REST returns a fixed structure. A profile screen needs name, avatar, email — the server sends 40 fields. Over-fetching. GraphQL solves this: the client requests exactly the needed fields. This is critical for mobile where traffic and parsing time are real constraints. Apollo iOS and Apollo Kotlin generate typed classes from schema: schema.graphql + query files → strict types at compile time. Subscriptions via WebSocket — real-time without polling. Limitation: GraphQL is harder to cache at the HTTP level. Apollo uses a normalized in-memory cache InMemoryNormalizedCache — requests with overlapping data update the cache without duplication.

WebSocket: Real-Time Without Extra Traffic

Polling (setInterval every 5 seconds) — battery and traffic waste. WebSocket is a persistent bidirectional connection. iOS: URLSessionWebSocketTask (native, iOS 13+). Android: OkHttp WebSocket. Mandatory reconnect handling: on onFailure — exponential backoff (1s → 2s → 4s → 8s → max 60s). Socket.IO is an overlay with automatic reconnect, but for new projects native WebSocket is preferable (fewer dependencies).

gRPC: For High-Load Services

gRPC with protobuf — binary serialization: smaller size, faster parsing. grpc-swift for iOS, grpc-kotlin for Android. The protobuf schema compiles to typed classes. Streaming (server-side, client-side, bidirectional) is a native feature. Application threshold: high request frequency (trading, IoT) or critical latency. For regular CRUD, REST is simpler to debug and monitor.

Certificate Pinning and Security

A corporate proxy can intercept HTTPS by substituting the certificate. Certificate pinning prevents this: the app accepts only a specific certificate or public key. Alamofire: ServerTrustManager with PinnedCertificatesTrustEvaluator. OkHttp: CertificatePinner with SHA-256 hash. Apple's App Transport Security documentation recommends pinning certificates for sensitive data. Operational complexity: on certificate rotation, older app versions stop working. Solution — pinning to the CA public key or support multiple pins with a grace period.

What Is Included in the Work

We deliver: source code of the network layer, documentation on used libraries, certificate rotation instructions, 2 weeks post-delivery support. Our experience guarantees that the solution will be stable and maintainable.

Timeline and Cost

Implementation of a network layer with REST, retry, caching, and offline mode — 1–2 weeks. Adding GraphQL or WebSocket — another 1–2 weeks. gRPC — 2–3 weeks, including code generation. The cost is calculated individually after analyzing the API and offline behavior requirements. We will evaluate the project in 1 day — contact us for a consultation. Get a reliable API integration with guaranteed quality.