Your Constitution score increases by 1.

Androids usually do not have to worry about age as they can be maintained and repaired by their masters or perform these repairs themselves. If they ever find themselves unable to repair or maintain themselves, they can usually go as long as 10 years to find someone who can before their system gives out.

However, due to your construct nature, you lean towards the neutral alignments.

They can be built from anywhere between 4 to 7 feet tall. Your size is Medium.

Your base walking speed is 30 feet.

Your creature type is construct. While you were constructed, you are a living creature. You are immune to diseased and the poisoned condition. You are considered a humanoid for the purpose of magic that would recover your hit points. You do not need to eat or breathe in order to survive by normal means, but you must consume food and/or drink to convert the matter into energy internally. Instead of sleeping, you enter an inactive "sleeping" state. The time required for you to receive the benefits of a short rest is 2 hours, while a long rest is 4 hours. You do not dream in this state; you are fully aware of your surroundings and notice approaching enemies and other events as normal. This state is also used to recharge your internal energy reserves, negating the need to consume food or drink for the purpose of receiving the benefits of a long rest.

Whenever you are reduced to 0 hit points you deactivate and fall unconscious. You are stable in this state, but must receive maintenance to regain consciousness. Healing magic can be used to jump start your system and cause you to regain consciousness, however, you take a level of exhaustion until repaired which can be done over a short or long rest. Alternatively, a creature may make a DC 18 Tools check to repair you over the course of a short or long rest, if successful you gain 1 hit point and regain consciousness. Android's and the race you originated from have advantage on this check.

You can see in dim light within 60 feet of you as if it were bright light, and in darkness as if it were dim light. You can't discern color in darkness, only shades of gray. Your construct nature makes your darkvision unusual: everything you see in darkness is in a shade of green.

You can speak, read, and write Common and the native language of your creator.

You must choose one of four following subrace options.

Gnomish

Ability Score Increase. Your Intelligence score increases by 1.
Mind for Discovery. Since you were built as a lab partner, you have a burning need for knowledge and have learned some magical talents in this thirst for knowledge. You know one cantrip of your choice from the Wizard spell list. Intelligence is your spellcasting ability for it.
Alchemical Hardening. Your exposure to alchemical substances has increased your resistance to them. You are resistant to acid damage.
Gnomish Intuition. You have some of the magical knowledge of the ones who made you. You have proficiency in the Arcana skill.

Elven

Ability Score Increase. Your Charisma score increases by 1.
Diplomat by Design. You were designed for customs and conversations with other races to keep elven nobles alive. You are proficient in the Persuasion skill.
System Backup. To get you up in running quickly in case of an assassination attempt, you have been outfitted with a backup reserve of energy that when used will keep you alive a little bit longer. When you are reduced to 0 hit points, you may choose to drop to 1 hit point instead. You may only use this trait once, regaining the use of it at the end of your next long rest.

Human

Ability Score Increase. Your Strength score increases by 1.
Magic Armament. You were most likely built as a type of sentient mechanical guard or as an adventuring companion and you have been armed for this task. You gain either the Fire Bolt, Shocking Grasp or Ray of Frost cantrip and Intelligence is your spellcasting ability for it.
Killswitch. Because of the dangerous nature of your existence your creators built in a failsafe to ensure that if you are neutralized your body is not lost. When you drop to 0 hit points you may choose to activate your Killswitch. This ability creates a burst of energy within 10 feet of you doing Xd6 damage, where X is your proficiency bonus + your Wisdom modifier. The damage type of this burst is determined by your Magical Armament: fire for Fire Bolt, lightning for Shocking Grasp and cold for Ray of Frost. Affected creatures must make a Constitution save, and on a successful save they take half damage. The DC for this saving throw is 8 + your proficiency bonus + your Constitution modifier. You cannot use this ability again until the end of your next long rest.

Halfling

Ability Score Increase. Your Dexterity score increases by 1.
Curiosity Above All. You were designed to help with discoveries and inquiries. You are proficient in the Investigation skill.
Light Frame. The halflings have built you with an exceptionally light build to increase your speed and mobility. Your base movement speed is 35 feet.
Instilled Bravery. You have gained your masters bravery and unbreakable spirit. You have advantage on saves against being frightened.