How to Make an App Like BlockFi

Crypto lending and interest-earning platforms changed the way people think about digital assets. Instead of letting Bitcoin or Ethereum sit idle in a wallet, users can deposit holdings, earn yield, borrow fiat against collateral, and trade — all from a single mobile interface. BlockFi popularised that model and proved there's a real appetite for "banking-style" products built on crypto rails.

If you're planning to build something similar, this guide walks through the product thinking, feature set, architecture, compliance requirements, cost drivers, and go-to-market decisions involved in launching a BlockFi-style app.

What Exactly Is an App Like BlockFi?

At its core, a BlockFi-style platform is a crypto financial services app that sits between retail users and the lending markets. It typically offers:

• Interest accounts — users deposit crypto and earn yield on their balances
• Crypto-backed loans — users pledge BTC/ETH as collateral and receive fiat or stablecoins
• Trading — simple swap functionality between supported assets
• Custody and wallets — secure storage of user funds
• Rewards products — cashback cards, referral bonuses, staking incentives

The business model is spread-based: the platform lends out deposited assets (to institutional borrowers, market makers, or through DeFi protocols) at a higher rate than it pays depositors, and pockets the difference. Loan origination fees, trading spreads, and withdrawal fees add secondary revenue.

Important context: BlockFi filed for bankruptcy in late 2022 following contagion from the collapse of several crypto lenders. Any modern take on this model must be built with far stronger risk management, transparency, and regulatory alignment than the first generation of platforms had. Treat this as a design constraint, not an afterthought.

Step 1: Validate the Model and Pick a Niche

Don't clone BlockFi feature-for-feature. Decide which wedge you're attacking:

Niche	Angle
Regional lending	Serve a market underserved by global platforms (LATAM, SEA, MENA)
Institutional-only	Higher ticket sizes, fewer compliance headaches than retail
DeFi-routed yield	Transparent, on-chain yield sources instead of opaque counterparties
Stablecoin savings	Lower volatility, easier to explain to mainstream users
Collateralised lending only	Skip the yield product entirely and focus on borrowing

Your niche determines your licensing burden, your liquidity partners, and your unit economics. Choose before you write a line of code.

Step 2: Nail the Regulatory Groundwork First

This is the step that kills most projects. In a crypto lending product, compliance isn't a feature — it's the foundation.

Typical requirements include:

• Entity structure and licensing — MSB/MTL registration in the US, VASP registration in the EU under MiCA, or licensing through jurisdictions like Singapore, Dubai (VARA), or Switzerland
• KYC/AML — identity verification, sanctions screening, PEP checks, ongoing transaction monitoring
• Securities analysis — interest-bearing accounts have been treated as unregistered securities in several jurisdictions. Get a legal opinion before launch.
• Custody rules — some regions require qualified custodians or segregated client assets
• Tax reporting — 1099s, transaction exports, and jurisdiction-specific reporting

Budget real money and real time here. Engage fintech counsel in every market you intend to operate in.

Step 3: Define the Feature Set

MVP Features

Onboarding and KYC

• Email/phone signup with 2FA
• Document capture and liveness check
• Tiered verification levels tied to transaction limits

Wallet and Custody

• Deposit addresses per asset
• Hot wallet for liquidity, cold/multi-sig storage for the bulk of funds
• Withdrawal whitelisting and time-locks

Interest Accounts

• Real-time or daily accrual display
• Tiered APY based on balance
• Clear, honest disclosure of where yield comes from

Crypto-Backed Loans

• Loan calculator with LTV selection (e.g., 20%, 35%, 50%)
• Collateral deposit flow
• Margin call and liquidation logic with user notifications
• Repayment schedule and early payoff

Trading / Swap

• Simple buy/sell/convert between supported assets
• Order preview with fees shown upfront

Transactions and Reporting

• Full ledger history with filters
• CSV/tax export
• Statements

Phase 2 Features

• Fiat on/off-ramps via ACH, SEPA, card, or local rails
• Crypto rewards debit/credit card
• Recurring buys and auto-invest
• Institutional dashboard and API access
• Referral and affiliate programme
• In-app education and market data

Step 4: Design the Architecture

A crypto lending platform is a distributed financial system. Plan accordingly.

Recommended Stack

Mobile front end

• React Native or Flutter for cross-platform speed
• Native Swift/Kotlin modules for secure enclave, biometrics, and key handling

Backend

• Microservices: auth, kyc, wallet, ledger, lending, pricing, notifications, reporting
• Go, Node.js, or Java for core services; Python for risk and analytics
• gRPC or REST between services, Kafka or RabbitMQ for events

Data layer

• PostgreSQL for the double-entry ledger (never store balances as a single mutable field)
• Redis for sessions, rate limiting, and price caching
• Time-series DB for market data and risk metrics
• Immutable audit log, append-only

Blockchain layer

• Node infrastructure or providers like Alchemy, Infura, QuickNode
• Custody via Fireblocks, Copper, BitGo, or self-built MPC using threshold signatures
• Chain listeners for deposit confirmation with configurable confirmation depth

Third-party integrations

• KYC/AML: Sumsub, Persona, Jumio, Chainalysis, Elliptic
• Pricing: CoinGecko, Kaiko, Chainlink oracles
• Banking: Circle, Fireblocks, or regional banking-as-a-service partners

The Ledger Is the Heart of the System

Use double-entry accounting from day one. Every deposit, accrual, loan disbursement, interest charge, liquidation, and withdrawal must be recorded as balanced debits and credits. This gives you:

• Reconciliation against on-chain balances
• Auditability for regulators and accountants
• Confidence that your liabilities never silently exceed your assets

Risk Engine

Your lending logic needs a dedicated risk service that:

1. Prices collateral continuously against reliable oracles
2. Recalculates LTV for every open loan on every price tick
3. Triggers margin call notifications at defined thresholds
4. Executes partial or full liquidations automatically
5. Enforces counterparty exposure limits and concentration caps
6. Stress-tests the book against historical drawdown scenarios

The 2022 crypto credit crisis happened largely because platforms lent unsecured to a small number of counterparties. Build hard limits into the system, not just into policy documents.

Step 5: Security Architecture

Security failures in this category are existential. Non-negotiables:

• Key management — MPC or HSM-backed signing, no single point of compromise
• Cold storage majority — keep 90%+ of assets offline with multi-party approval flows
• Withdrawal controls — whitelisting, 24–48h delays on new addresses, velocity limits
• Application security — certificate pinning, jailbreak/root detection, obfuscation, secure enclave storage
• Infrastructure — least-privilege IAM, network segmentation, secrets management, immutable infrastructure
• Monitoring — anomaly detection on withdrawals, real-time alerting, SIEM
• Audits — annual penetration tests, smart contract audits if you touch DeFi, SOC 2 Type II

Also plan for proof of reserves. Post-FTX, users expect cryptographic evidence that their assets exist. Merkle-tree attestations plus a third-party auditor should be on the roadmap.

Step 6: UX Considerations

Crypto finance apps fail when they assume users understand crypto finance. Good UX here means:

• Plain-language yield explanations — where does the APY come from, and what are the risks?
• Transparent liquidation mechanics — show users exactly at what price they get liquidated, with a visual gauge
• Progressive disclosure — hide gas settings, network selection, and advanced options behind "Advanced"
• Confirmation friction on irreversible actions — address confirmation, amount re-entry, biometric approval
• Empty states that teach — the first-run experience should educate, not just prompt a deposit
• Honest risk labelling — no "guaranteed returns" language, ever

Step 7: Build, Test, and Launch

Suggested Timeline

Phase	Duration	Output
Discovery and legal	6–10 weeks	Market analysis, licensing plan, product spec
UX/UI design	6–8 weeks	Flows, prototypes, design system
Core backend and ledger	10–14 weeks	Auth, KYC, ledger, wallet services
Mobile apps	12–16 weeks	iOS and Android MVP
Lending and risk engine	8–12 weeks	Loan lifecycle, liquidations
Security audit and QA	6–8 weeks	Pen test, remediation, load testing
Beta and launch	4–8 weeks	Closed beta, phased rollout

Realistically, 9 to 15 months to a compliant public launch, with significant overlap between phases.

Testing Priorities

• Testnet integration for all chain operations
• Deterministic simulation of price crashes and mass liquidations
• Chaos testing on deposit/withdrawal paths
• Reconciliation jobs that verify ledger against chain state hourly
• Load testing for market-volatility traffic spikes (expect 10–20x normal)

Step 8: Estimating Cost

Costs vary enormously with licensing scope and custody approach.

Component	Indicative Range (USD)
Legal, licensing, entity setup	$80k – $500k+
Product design	$30k – $70k
Mobile apps (iOS + Android)	$90k – $180k
Backend, ledger, integrations	$120k – $250k
Risk and lending engine	$60k – $120k
Security audits and pen testing	$30k – $80k
Custody / infrastructure (annual)	$50k – $200k
Total for a compliant MVP	$400k – $1.2M+

Ongoing operations — compliance staff, treasury management, customer support, insurance — typically run $40k–$150k per month at modest scale.

Step 9: Monetisation and Growth

Revenue levers

• Net interest margin between borrow and lend rates
• Loan origination fees (1–2%)
• Trading spread (0.5–1%)
• Withdrawal fees
• Interchange on a rewards card
• Premium tiers for higher APY or lower fees

Growth tactics

• Referral programmes with crypto rewards
• Content and education as the top of funnel
• Partnerships with exchanges and wallets
• Transparency as marketing — publish reserves, yield sources, and risk policies

Common Pitfalls to Avoid

1. Treating compliance as a phase two problem. It defines your architecture.
2. Opaque yield. If you can't explain where returns come from in one sentence, users shouldn't trust it — and regulators won't either.
3. Unsecured counterparty lending. The single biggest cause of failures in this sector.
4. Single-signature hot wallets. One compromised key ends the company.
5. Mutable balance fields. Without a proper ledger, you cannot audit or recover from incidents.
6. Ignoring liquidity management. Model withdrawal runs before they happen.
7. Over-promising in marketing copy. "Up to X% APY" with clear risk disclosure, never "guaranteed."

Final Thoughts

Building an app like BlockFi is less of a mobile development project and more of a regulated financial institution that happens to have an app. The UI is the easy part. The hard parts are custody, risk, liquidity, and licensing — and those are exactly the areas where the first generation of crypto lenders came up short.

If you approach it with a transparency-first product, conservative risk parameters, real regulatory cover, and institutional-grade security, there is still a substantial and underserved market for crypto-native financial services. The opportunity hasn't gone away; the tolerance for cutting corners has.

Start with a narrow, defensible niche. Build the ledger and risk engine before the marketing site. And make transparency your differentiator, not your compliance checkbox.

Have a project in mind? Contact Sodio Technologies to discuss your requirements and explore the right technology solution for your business.