Edit in JSFiddle

var map = $('#map'),
    info = $('#info'),
    m = {};

map.tinyMap({
    center: { x: '25.037467', y: '121.564077' },
    // 自訂縮放控制
    zoomControlOptions: {
        'style': 'LARGE',
        'position': 'RIGHT_TOP' // 將縮放拉桿放到右邊
    },
    marker: [
        {
            id: 'm01', 
            addr: ['25.037467', '121.564077'], 
            text: 'marker01' ,
            label: 'marker01',
            css: 'label'
        },
        {
            id: 'm02', 
            addr: ['25.100295', '121.549494'], 
            text: 'marker02',
            label: 'marker02',
            css: 'label'
        },
        { 
            id: 'm03', 
            addr: ['25.033570', '121.564773'], 
            text: 'marker03',
            label: 'marker03',
            css: 'label'
        }
    ],
    zoom: 16,
    /**
     * 綁定地圖事件
     * 完整事件可以參考 
     * https://developers.google.com/maps/documentation/javascript/reference?hl=en-us#Map
     */
    event: {
        // 縮放等級變動事件
        'zoom_changed': function (e) {
            var m = map.data('tinyMap'),
                bounds = m.map.getBounds(), //取出目前範圍
                markers = m._markers, //取出所有標記
                marker = {},
                inrange = [],
                i = 0,
                msg = '';
            
            msg += '目前縮放等級: ' + m.map.getZoom();
            
            for (i = 0; i < markers.length; i += 1) {
                marker = markers[i];       
                // 逐一判斷標記是否在範圍內
                if (bounds.contains(marker.position)) {
                    inrange.push(marker.infoWindow.content);                    
                }
            }            
            msg += '<br />目前可視標記:<br />' + inrange.join('<br />') + '</p>';
            info.html(msg);
        }
    }
});

<div id="info">&nbsp;</div>
<div id="map"></div>    
<button id="getBounds">取得範圍內的 Markers</button>

#map{width: 100%;height:240px}
#info{background:#eee;margin-bottom:6px}
.label{background-color:rgba(0,0,0,0.8);color:#fff;padding:3px}