1. One of the foremost differences between the two is that HTC Desire 820 is a dual sim phone, whereas Samsung Galaxy S4 is not.
2. Galaxy S4’s operating system (OS) is Android v.4.2 (KitKat) and upgradable to Lollipop . HTC Desire 820 features Android v4.4.2 (KitKat).
3. Samsung Galaxy S4 defeats HTC Desire 820 when it comes to resolution. It has 125% more pixels as compared to its competitor. Galaxy S4 boasts a resolution of 1080×1920. While Desire 820’s resolution is 720×1280.
4. Talking about multimedia features, the HTC phone supports MMS. In addition to MMS, the Samsung phone offers Calendar, Voice Commands, Instant Messaging and YouTube Player.
5. Samsung Galaxy S4 is lighter than the other one. It weighs 130 grams, while its rival hits the scales at 155 grams. HTC Desire 820 is about 16% heavier.
6. Among sensors, both the models have compass and accelerometer. The additional sensor in Samsung Galaxy S4 is gyroscope.
7. HTC Desire 820 has 1.7 GHz Octa core CPU, while Samsung has incorporated 1.6 GHz Quad core into Galaxy S4. The greater the number of cores, the better is the parallelism. This implies that Desire 820 is capable of performing more number of tasks simultaneously, without making user interface slow.
8. Samsung Galaxy S4 has removable battery. This function is absent in the other phone. When the phone has removable battery, the user can remove the battery when it degrades and replace it with another one. Yet another use is to remove the battery in order to switch off the phone in case it freezes, something called hard reset.
9. Galaxy S4 has a 5 inch screen. Desire 820 has a slightly bigger screen of 5.5 inches. The latter possesses 5% bigger screen than the former one, which is more comfortable while browsing the internet, reading on the screen, watching movies etc.
10. Samsung Galaxy S4 features HDMI support, a feature absent in Desire 820. With this facility, HDMI cable can be used and the user can stream videos and photos to their LCD TV.
11. HTC Desire 820 has FM radio, whereas Galaxy S4 users are deprived of this feature.
12. Yet another aspect is the battery standby time. Samsung Galaxy S4 has battery standby time equal to 370 hours. This figure is 424 hours in case of HTC Desire 820. The latter has 14% longer battery standby time than the former. This implies that its battery can last longer without requiring charging.
13. Samsung Galaxy S4 supports a useful feature called NFC, that is absent in HTC Desire 820. With this feature, the user can make wireless payments by using the phone. Another interesting use is that connection can be established between two NFC enabled devices simply by touching them with one another.
14. Desire 820’s battery talk time is longer when compared with that of Galaxy S4. Desire has a battery talk time of 1320 minutes, while the other’s battery talk time is 1020 minutes. This is a difference of about 29%. Users of HTC Desire 820 can talk for a longer time on the phone without having to charge it.
15. Both have 13 MP camera along with autofocus. Face detection, Touch to focus and Geo tagging too are the features that both the models share. An additional feature present in the Samsung phone is Smile detection.
16. The front camera of Galaxy S4 is of 2 MP only, but it supports video calling. Desire 820 boasts front camera of 8 MP.
So , Samsung S4 is a best choice for those who are searching for a smart phone at range of Rs 17500 -20,000