realme P4s Lite vs realme C100i vs Infinix SMART 20 HD: which budget 4G phone, or should you go 5G?

Three new budget phones are chasing the same buyer this festive season, and they share more than a price bracket. The realme P4s Lite, the realme C100i and the Infinix SMART 20 HD all run on the same Unisoc T7250 chip, all have 120Hz HD+ screens, and none of them supports 5G. So the differences come down to battery, memory, cameras and price.

Here is how they compare, using each brand's official spec page and the prices listed on Flipkart and the Infinix store (price as of 8 October 2026, 1:25 AM IST). At the end, we look at whether it is worth stretching to a 5G phone such as the Redmi 17C 5G instead.

Prices first

The Infinix SMART 20 HD is the cheapest at Rs 10,999 for 3GB of RAM and 64GB of storage, on both the Infinix store and Flipkart. The store showed it as sold out when we checked.

The realme P4s Lite costs Rs 14,999 for 4GB and 64GB, and Rs 16,999 for 4GB and 128GB, on Flipkart.

The realme C100i costs Rs 16,499 for 4GB and 64GB on Flipkart. A 4GB and 128GB version is listed on realme's spec page.

Flipkart shows much higher struck-through MRPs on all of these. Ignore them. The selling price is what you are comparing.

Same chip, so performance is a wash

All three use the Unisoc T7250 with a Mali-G57 GPU. Infinix lists it as two Cortex-A75 cores at 1.8GHz and six Cortex-A55 cores at 1.6GHz. In daily use, expect these phones to feel similar for calls, WhatsApp, YouTube and light games. None of them is built for heavy gaming.

Memory is where they split. Both realme phones use LPDDR4X RAM and UFS 2.2 storage, according to realme. The Infinix has only 3GB of RAM, though it can borrow storage to extend it to 6GB. Virtual RAM helps a little with keeping apps open, but it is no substitute for real memory. If you switch between many apps, the realme phones have the edge.

Battery: the realme P4s Lite leads

This is the clearest difference. realme lists the P4s Lite at 7000mAh typical (6820mAh rated) and the C100i at 6500mAh typical (6300mAh rated). Infinix lists 5000mAh for the SMART 20 HD. All three charge at 15W, which means slow refills, especially for the 7000mAh phone.

realme also claims the P4s Lite battery will keep more than 80% of its capacity after six years, based on its own lab simulation. That is a brand claim, but it is a specific one, and the bigger capacity is real. If you want a phone that lasts two days, the P4s Lite is the pick. Our explainer on typical vs rated battery capacity explains why each brand quotes two figures.

Screens and cameras

The C100i has the largest screen at 17.3cm (about 6.8 inches), against 17.15cm (6.75 inches) on the P4s Lite and 6.67 inches on the Infinix. Both realme phones list 700 nits typical and 900 nits in high brightness mode, and Panda MN228 glass. Infinix lists 560 nits typical and 700 nits peak.

On cameras, the P4s Lite has a 13MP rear camera with autofocus, while the C100i has an 8MP rear camera with autofocus. Both have 5MP front cameras. The Infinix has 8MP cameras on both sides and adds a front flash, which is handy for selfies in poor light. None of these will impress in low light, and the realme phones top out at 1080p video at 30fps, according to realme.

Other details worth knowing

All three have a 3.5mm headphone jack and a microSD slot. The P4s Lite carries IP64 dust and splash protection, according to realme's product page, as does the Infinix. The Infinix adds dual speakers with a 300% volume mode and Ultra Link, which lets Infinix phones call and message each other within about 200 metres without a network. The P4s Lite weighs 215g and the C100i 210g, so both are on the heavy side.

Which one should you buy?

For most people, the realme P4s Lite at Rs 14,999 is the best of the three. It has the biggest battery, a better rear camera than the C100i and costs less than it. Pay Rs 2,000 more for the 128GB version if you can.

The C100i is hard to justify at Rs 16,499 when the P4s Lite is cheaper with a bigger battery. It would only make sense if its price drops below the P4s Lite during a sale.

The Infinix SMART 20 HD makes sense at Rs 10,999 as a backup phone or a first phone for a parent who mostly calls and watches videos. The 3GB of RAM rules it out as a main phone for a heavy user.

Or should you stretch to 5G?

That is the real question. Xiaomi's Redmi 17C 5G starts at Rs 20,999 on mi.com, as we found in our Redmi 17C 5G vs Redmi 17 5G comparison. For about Rs 6,000 more than the P4s Lite, you get 5G, a 6000mAh battery with faster 33W charging and a MediaTek Dimensity 6300 chip.

If you plan to keep the phone for three years or more, that extra money is worth it. 4G will keep working, but more of what you do on the network will be built around 5G. If your budget is fixed at Rs 15,000, the P4s Lite is a sensible buy today. If you can stretch, look at a 5G phone. Our report on the Lava Shark 2 Pro 5G at Rs 16,699 shows there are 5G options closer to the Rs 15,000 mark too. Official specs are on the realme P4s Lite, realme C100i and Infinix SMART 20 HD pages.