B4X

B4X is a family of rapid-development tools for mobile, desktop, server and embedded applications. It is best for developers who want focused tools for each target while sharing most code between projects. The trade-off is that iOS work requires Apple hardware or a hosted builder arrangement, plus Apple’s separate developer fee.

Overview

B4X splits development by destination: B4A for Android, B4i for iOS, B4J for desktop and server software, and B4R for Arduino, ESP8266 and ESP32 boards. The maker says applications compiled for iOS, Android, Arduino and ESP8266 are native and dependency-free. It also claims B4A, B4J and B4i projects can share 90% or more of their code through cross-platform libraries, which can substantially reduce duplicated work in a multi-platform product.

The B4X language is presented as a modern form of Visual Basic, with Java also supported. That combination will appeal to developers coming from those languages; teams seeking a single mainstream cross-platform stack may find the split-tool approach less familiar. Anywhere Software says it has focused on mobile development since 2005.

Key features

Mobile tools

B4A provides a visual GUI designer for multiple screens and orientations, and supports debugging through USB or a wireless bridge. Those are useful for Android developers handling varied device layouts and testing without being tied to a cable. B4i covers iOS, but its workflow has firm prerequisites: an Apple developer account, an iOS 11-or-newer device, and Windows 7 64-bit or a virtual machine for the IDE. The hosted Mac Builder accepts projects up to 50 MB, so larger iOS projects need another build arrangement.

Desktop, server and IoT

B4J goes beyond desktop interfaces to console programs and server solutions. Its applications can run on Windows, Mac, Linux and ARM boards such as Raspberry Pi, giving one tool a broad deployment range. B4R targets Arduino, ESP8266 and ESP32 hardware; its setup uses Arduino IDE version 2 and Arduino CLI. B4R libraries are open source under the MIT license, with code published on GitHub.

Development workflow

Visual UI design, emulator or simulator support and application packaging are included capabilities. The combination of native output and substantial code sharing is most valuable when a small team must reach several targets without maintaining entirely separate implementations.

Pricing

B4A, B4R and B4J are free, including commercial use. B4A Standard and B4i Standard each cost 59.00 USD once per developer and include two months of free upgrades. B4i Standard with the hosted Mac Builder costs 85.00 USD once per developer and adds one year of hosted-builder service. Enterprise editions cost 119.00 USD once per developer, with two years of free upgrades; the B4i version with one year of hosted Mac Builder costs 145.00 USD.

B4A Site costs 599.00 USD once for up to 30 developers on one site and includes two years of free upgrades. Licenses are perpetual and applications made with B4A, B4i or B4J are royalty free. iOS developers must separately budget the Apple developer account at 99 USD per year. There is no free trial, so the free Android, desktop/server and embedded tools are the practical way to evaluate the ecosystem before buying.

Platforms

B4X targets Android and iOS on mobile, Windows, macOS and Linux on desktop, and server and ARM-board deployments through B4J. B4R covers Arduino, ESP8266 and ESP32 hardware. Java and B4X are supported languages.

Who it's for

B4X suits independent developers and small teams that need Android, iOS and desktop or server companions, particularly when sharing 90% or more of code can offset the cost of maintaining several targets. It is also a strong fit for embedded projects that benefit from a dedicated microcontroller tool and MIT-licensed libraries. Android-only, desktop/server and Arduino users can start at no software cost. iOS-focused teams should accept the Apple-account requirement, device requirement and 50 MB hosted-builder ceiling before committing.

Pros and cons

Pros

• Free core tools: B4A, B4R and B4J are free even for commercial development.
• Broad target coverage: Separate tools span mobile, desktop, servers, Raspberry Pi-class boards and microcontrollers.
• High code reuse: B4A, B4J and B4i can share 90% or more of their code through cross-platform libraries.
• Predictable licensing: Paid licenses are perpetual, per developer, and B4A, B4i and B4J applications are royalty free.

Cons

• iOS overhead: Apple’s 99 USD annual account, an iOS 11+ device and Windows 7 64-bit or a VM add requirements beyond the B4i license.
• Hosted-builder cap: The Mac Builder supports projects only up to 50 MB.
• Per-developer pricing: Larger teams need the 599.00 USD site license or multiple individual licenses.
• No trial: Paid editions cannot be evaluated through a time-limited trial.

Alternatives

Choose Codename One if Java-based development, web output and a free monthly cloud-build allowance are more important; its free plan includes 100 cloud build credits per month but limits iOS builds to eight credits each.

Defold is the better pick for a completely free tool with no licensing, royalty or runtime fees.

Choose Felgo when a commercial freemium plan and web-capable targets fit your budget; its Startup plan is €79 a month when billed annually.

Godot Engine suits teams wanting a free, open-source engine with no contracts or hidden fees.

Solar2D is an alternative free mobile-focused framework with no engine fees or royalties.

DroidScript fits Android-first experimentation with optional paid plugins.

Monaca is preferable if a cloud IDE, three projects and three remote builds per 24 hours are useful on its free plan.

Qt Creator is worth considering when Qt’s open-source or commercial licensing model matches your application and platform needs.

For a wider shortlist, see Mobile Development IDEs.

Verdict

Choose B4X if you want free Android, desktop/server and embedded tools, native output and unusually high code reuse across a broad set of targets. Look elsewhere if iOS is central and the Apple account, device, Windows-or-VM requirement or 50 MB hosted-builder limit conflicts with your workflow, or if you need a conventional single-tool stack with a trial.