
I having been exploring Ubin with a GPS for a number of years. GPS devices like Garmin uses free satellite signals and all you need is the AA batteries to power them. With backlighting on full, they last about 8 hours so its important to carry fresh backup batteries. I am using Sanyo Eneloop rechargeable batteries which performs better.
Basic GPS functions.
Its perhaps unfortunate that GPS is full of geek stuff. The simplest function is to learn how to create breadcrumbs (‘waypoints’ or ‘landmarks’) on key trail features such as junctions, bridges or buildings for simple navigation.
As jungle trails are often featureless and following a winding path, next up in complexity is to learn how to set track logs. All you need is to set the GPS to record your trails as you walk. In the jungle, your trails appears zig-zagged looking like a bird nest due to inaccuracies due to tree cover. The track logs are then downloaded with free software to clean them. Once cleaned, the tracks can be uploaded back to the GPS for use later or shared online.
Track logs are also useful to embed GPS co-ordinates into your digital photos using GPISync, a freeware from Google. This way, you don’t have to tether your camera to a GPS or purchase a dedicated camera GPS which are usually inferior in terms of accuracy.
GPS recommendations.
My favorite GPS model was Garmin 60CSx which is compact and popular. It has since been updated with 62 series. With its buttons layout it is easy to access frequently used functions but typing names of places is difficult. For that, I bought a Garmin Oregon 450 GPS which uses a touch-screen interface. The cons for Oregon is the dim screen in daylight. Its big brother, Garmin Montana has a bright and large screen which serve its dual function as a in-vehicle navigator. Having tried all, my preference is Garmin 62s for its secure grip, followed by Oregon 450 for its touch-screen and compact size. The shop I usually buy from is Perfect Watch at Level 1, Sim Lim Square.
GPS Software.
Software like Google Earth, Garmin Basecamp allow you to clean your track logs or plan your hike in advance. New Garmin models are able to load satellite images by subscribing to Garmin BirdsEye™ Satellite Imagery. The annual subscription costs is US$30. The subscription is worthwhile as I am able to download detailed images for Pulau Ubin. I am now able to confirm position of visible landmarks with better accuracy. Its would have been a chore to take multiple readings 90 minutes apart. I found out earlier that Google Earth images are not accurately positioned and cannot be relied upon.
Sharing maps online.
The problem with GPS is the babel of formats limiting its usefulness. Fortunately times have changed and formats like Google Earth KML are becoming popular, allowing users to share their maps on-line.
Watch this space. I will be adding more tracks and locations of interesting places. You can also download the kml file and view it on Google Earth. With a bit of technical know how, you should also be able to download them into your GPS unit for your next trip to Ubin.
Ubin on GoogleMaps
Download Google earth kml file Updated 01 Mar 2009

Download Free Google Earth Software
Other GPS features to consider.
More advanced units allow you to download routable maps that provide driving directions. Garmin users are able to download free routable maps for Singapore and Malaysia.
There is a profusion of smartphones with similar GPS functions. I pay little attention to such 3G subscription based phones. Overseas telecos are scamming the public with exorbitant phones bills. I was in Dubai when I accessed its 3G for less than a minute before turning off the phone and was slapped with $700 phone bill. You are in luck if you have a Symbian S60v3 smartphone such as Nokia E71 or E72. Garmin have a navigation software called Garmin Mobile XT. With pre-loaded maps you do not have to incur expensive data charges. I installed it on my Nokia E72 which have built-in GPS and compass, albeit mickey-mouse in performance. Took as much as 20 minutes to locate satellites. Went to my favorite online site and ordered a Holux bluetooth M-1000 GPS to pair with my mobile. Results looks good with bonus voice prompt.
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Update: 11 July 2010. Negative experience with VPost.
Ordered the Oregon 450 after reading positive reviews. Purchased from Amazon online which includes free shipping. My intention is to get it shipped to Vpost USA address who will then ship to Singapore with attractive shipping rates at one third the shipping costs. Shipping direct would have costs me US$90 instead. The only con is slower transit time but I am prepared to wait.
Turns out to be a mistake. Vpost’s service is abysmal. First they refused to accept the shipment while its on its way. They claimed it contains batteries and is therefore considered as dangerous cargo even though Garmin do not ship batteries with their GPS. I have to write a letter twice to them together with description of the packing contents stating it contains no batteries. Next Vpost lost the shipment after USPS delivered it to them. I have to give them USPS tracking number thrice. Took them 2 weeks to tell me they do not have my shipment, giving me a one liner reply asking me to contact USPS myself. A note from them that they checked with USPS with no avail would have helped me claim a refund from Amazon. Disheartened I wrote to Amazon to help me trace my shipment with USPS and within 12 hrs Amazon wrote to me that it considered the shipment as lost and immediately refunded me. No questions asked. Amazon has my customer loyalty. Not for Vpost.