A wheeled board device with forward and rearward in-line wheel structures attached to a user platform. The forward wheel may have a forward tilt axle or be otherwise direction-biased to permit lean-based turning. The rear wheel may be singular or comprise two tires or the like and be motorized or not. The wheels are preferably large to more readily handle surface irregularities. A self-balancing wheelie mode is disclosed in one embodiment. Other embodiments include placement of the forward tilt axle within or without the envelope of the front wheel. The user platform is below the top of the rear wheel and preferably near the axis of the rear wheel, among other features.